Ch.12 SystemsofEquationsandInequalities
12.1 SystemsofLinearEquations:SubstitutionandEliminatio
n
1 SolveSystemsofEquationsbySubstitution
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Verifythatthevaluesofthevariableslistedaresolutionsofthesystemofequations.
1)
x+y=2
x–y=4
x=3,y=–1
A) solution B) notasolution
2)
x+y=8
x–y=2
x=–5,y=3
A) solution B) notasolution
3)
3x+y=–12
2x+3y=–22
x=–2,y=–6
A) solution B) notasolution
4)
4x+y=18
3x+4y=20
x=4,y=–2
A) solution B) notasolution
Solvethesystemofequationsbysubstitution.
5)
x+y=–8
x–y=18
A) x=5
,
y=–13;(5
,
–13) B) x=5
,
y=13;(5
,
13)
C) x=8
,
y=–13;(8
,
–13) D) x=8
,
y=5;(8
,
5)
6)
x+7y=-
2
3x+y=34
A) x=12,y=–2;(12,–2) B) x= –2,y=3;(–2,3)
C) x=3,y=7;(3,7) D) x=7,y=12;(7,12)
7)
x+2y=2
7x–8y=-
8
A) x=0,y=1;(0,1) B) x=1,y=0;(1,0) C) x=1,y=1;(1,1) D) x=0,y=0;(0,0)
Page1
8)
5x–2y=–1
x+4y=35
A) x=3,y=8;(3,8) B) x=3,y=9;(3,9) C) x=2,y=8;(2,8) D) x=2,y=9;(2,9)
9)
2x+4y =10
2x =-
6
A) x=–3
,
y=4;(–3
,
4) B) x=4
,
y= –3;(4
,
–3)
C) x=–3
,
y=–4;(–3
,
–4) D) x= –4
,
y=0;(–3
,
0)
10)
5x+3y=80
2x+y=30
A) x=10,y=10;(10,10) B) x=0,y=10;(0,10)
C) x=10,y=0;(10,0) D) x=0,y=0;(0,10)
11)
3x+y=0
–3x+y=–6
A) x=1,y=–3;(1,–3) B) x= –1,y=3;(–1,3)
C) x=1,y=6;(1,6) D) x= –1,y= –3;(–1,–3)
12)
x+y=0
2x+3y=–7
A) x=7,y=–7;(7,–7) B) x= –7,y=7;(–7,7)
C) x=6,y=–6;(6,–6) D) x= –6,y=6;(–6,6)
13)
3x+y=13
2x–7y=24
A) x=5,y=–2;(5,–2) B) x= –5,y=2;(–5,2)
C) x=5,y=2;(5,2) D) x= –5,y= –2;(–5,–2)
14)
1
5x–y=–4
5
x+8y=–4
A) x=–4,y=0;(–4,0) B) x=4,y=0;(4,0)
C) x=0,y=–4;(0,–4) D) x=0,y=4;(0,4)
15)
1
2x+2
3y=32
1
4x–5
9y=40
A) x=100,y=–27;(100,–27) B) x=100,y=27;(100,27)
C) x=–100,y=–27;(–100,–27) D) x= –100,y=27;(–100,27)
Page2
16)
2x+9y=–8
x+ 1
3y=13
3
A) x=5,y=–2;(5,–2) B) x= –5,y=2;(–5,2)
C) x=5,y=2;(5,2) D) x= –5,y= –2;(–5,–2)
2 SolveSystemsofEquationsbyElimination
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequationsbyelimination.
1)
5x+36y=36
3x–9y=-
9
A) x=0,y=1;(0,1) B) x=1,y=0;(1,0) C) x=1,y=1;(1,1) D) x=0,y=0;(0,0)
2)
5x–2y=–1
x+4y=35
A) x=3,y=8;(3,8) B) x=3,y=9;(3,9) C) x=2,y=8;(2,8) D) x=2,y=9;(2,9)
3)
x+y=-
5
x–y=17
A) x=6
,
y=–11;(6
,
–11) B) x=6
,
y=11;(6
,
11)
C) x=5
,
y=–11;(5
,
–11) D) x=5
,
y=6;(5
,
6)
4)
5x+4y=74
5x+2y=82
A) x=18
,
y=–4;(18
,
–4) B) x= –18
,
y=5;(–18
,
5)
C) x=–18
,
y=4;(–18
,
4) D) x= –4
,
y=18;(–4
,
18)
5) 6x+3y=51
2x–6y=38
A) x=10,y=–3;(10,–3) B) x= –3,y=10;(–3,10)
C) x=–10,y=3;(–10,3) D) x=3,y= –10;(3,–10)
6) 3x–5y=-
12
6x+8y=-
24
A) x=–4,y=0;(–4,0) B) x=4,y=0;(4,0)
C) x=0,y=–4;(0,–4) D) x=0,y=4;(0,4)
7)
2x+6y=-
36
12x+2y=90
A) x=9
,
y=–9;(9
,
–9) B) x= –9
,
y=9;(–9
,
9)
C) x=12
,
y=–12;(12
,
–12) D) x= –2
,
y=9;(–2
,
9)
Page3
8)
5x+3y=80
2x+y=30
A) x=10,y=10;(10,10) B) x=0,y=10;(0,10)
C) x=10,y=0;(10,0) D) x=0,y=0;(0,0)
9)
7
12x–y=10
5
9x+2y=11
A) x=18,y=1
2;18,1
2B) x=16,y=1
2;16,1
2
C) x=–18,y=–1
2;–18,–1
2D) x=–16,y=–1
2;–16,–1
2
10)
3
5x+2
5y=51
5
6x+2y=108
A) x=19
,
y=–3;(19
,
–3) B) x= –19
,
y=6;(–19
,
6)
C) x=–19
,
y=4;(–19
,
4) D) x= –3
,
y=19;(–3
,
19)
Solvethesystemofequations.[Hint:Letu=1
xandv=1
y,andsolveforuandv.Thenletx=1
u,andy=1
v.]
11)
2
x
+4
y
=7
1
x
–2
y
=4
A) x=4
15,y=–8;4
15,–8 B) x=15
4,y=–1
8;15
4,–1
8
C) x=–8,y=4
15;–8,4
15 D) x=–1
8,y=15
4;–1
8,15
4
Solvetheproblem.
12) Aflatrectangularpieceofaluminumhasaperimeterof68 inches.Thelengthis10incheslongerthanthe
width.Findthewidth.
A) 12in. B) 22in. C) 32 in. D) 34in.
13) TheFamilyFineArtsCentercharges$25 peradultand$10 perseniorcitizenforitsperformances.Ona
recentweekendeveningwhen534peoplepaidadmission,thetotalreceiptswere$7980.Howmanywho
paidwereseniorcitizens?
A) 358seniorcitizens B) 176seniorcitizens C) 268 seniorcitizens D) 266 seniorcitizens
14) Aretiredcouplehas$140,000toinvesttoobtainannualincome.Theywantsomeofitinvestedinsafe
CertificatesofDeposityielding7%.TheresttheywanttoinvestinAAbondsyielding10%peryear.How
muchshouldtheyinvestineachtorealizeexactly$12,800peryear?
A) $100,000at10%and$40,000at7% B) $100,000 at7%and$40,000at10%
C) $90,000at7%and$50,000at10% D) $110,000 at10%and$30,000at7%
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15) Atourgroupsplitintotwogroupswhenwaitinginlineforfoodatafastfoodcounter.Thefirstgroup
bought8slicesofpizzaand4softdrinksfor$36.60.Thesecondgroupbought7slicesofpizzaand4soft
drinksfor$32.67.Howmuchdoesonesliceofpizzacost?
A) $3.93persliceofpizza B) $1.29 persliceofpizza
C) $3.43persliceofpizza D) $1.79 persliceofpizza
16) Amovietheatercharges$8.00foradultsand$5.00forchildren.Iftherewere40peoplealtogetherandthe
theatercollected$272.00attheendoftheday,howmanyofthemwereadults?
A) 24adults B) 10adults C) 16adults D) 29adults
17) An8–cylinderCrownVictoriagives18milespergallonincitydrivingand21milespergalloninhighway
driving.A300–miletriprequired15.5gallonsofgasoline.Howmanywholemilesweredriveninthecity?
A) 153mi B) 147mi C) 132mi D) 168mi
18) ThePaperbackTraderisabookstorethattakesinusedpaperbacksfor20%oftheircoverpriceandsells
themfor50%oftheircoverprice.Patbringsinastackof17paperbackbookstotradeandgets$18.83
credit.Someofthebookshadacoverpriceof$6.95,therest$4.95.ShewantstogetsomeTomClancy
bookshavingacoverpriceof$6.95.Howmany$6.95booksdidshebringinandhowmanyClancybooks
canshegetwithoutpayinganyadditionalcash?
A) 5$6.95books,5Clancybooks B) 12 $6.95 books,2Clancybooks
C) 5$6.95books,6Clancybooks D) 5 $6.95 books,2 Clancybooks
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
19) Theperimeterofaparkinglotis500yards.Findthedimensionsofthelotifthelengthis50yardsmore
thanthreetimesthewidth.
20) Astorehasasaleonworkoutgear.MarkboughtthreepairsofshortsandthreeT–shirtsfor$70.35(before
tax).Later,hewentbackandboughttwomorepairsofshortsandfourmoreT–shirtsfor$63.90(before
tax).HowmuchdidtheshortsandT–shirtscost?
21) Ateashopownerismixingablendoftwoteas,oneofwhichcosts$6.50perpound,theothercosting$4.00
perpound.Theownerwantstohave20poundsofamixturethatwillsellfor$5.50perpound.Howmuch
ofeachtypeofteashouldbeused?
22)
ayahas$16,000toinvest.Sheinvestspartofitinanaccountpaying6%simpleinterestandtherestinan
accountpaying7%simpleinterest.Ifherannualincomeis$1080,howmuchdoesshehaveinvestedin
eachaccount?
23) Aboatonarivergoes77milesdownstreamin2hoursand45minutes.Thereturntriptakes3hoursand
30minutes.Iftheboatʹsspeedisthesameineachdirection,findthespeedoftheboatandthespeedofthe
current.
3 IdentifyInconsistentSystemsofEquationsContainingTwoVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequations.Ifthesystemhasnosolution,saythatitisinconsistent.
1)
x+y=–6
x+y=2
A) x=0,y=0;(0,0) B) x= –6
,
y=2;(–6
,
2)
C) x=0,y=–4;(0,–4) D) inconsisten
t
Page5
2)
x–4y=–10
2x–8y=–17
A) x=2,y=4;(2,4) B) x=2,y=3;(2,3) C) x=4,y=2;(4,2) D) inconsisten
t
3)
4x–7y=1
4x–7y=–9
A) x=4
,
y=7;(4
,
7) B) x=1
,
y= –9;(1
,
–9)
C) x=1
7,y=–9
4;1
7,–9
4D) inconsisten
t
4)
4x–6y=6
8x–12y=30
A) x=2
,
y=5;(2
,
5) B) x=3
,
y= – 2;3
,
2
C) x=6
,
y=30;(6
,
30) D) inconsisten
t
5)
5x–9y=6
–20x+36y=–18
A) x=5
,
y=6;(5
,
6) B) x=5
4,y=–9
4;(5
4,–9
4)
C) x=4
,
y=3;(4
,
3) D) inconsisten
t
4 ExpresstheSolutionofaSystemofDependentEquationsContainingTwoVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequations.Ifthesystemhasnosolution,saythatitisinconsistent.
1)
x+7y=5
2x+14y=10
A) y=–x
7
+5
7,wherexisanyrealnumber
or{(x,y)|y=–x
7
+5
7,wherexisanyrealnumber}
B) x=0,y=0;(0,0)
C) x=5
,
y=0;(5
,
0)
D) inconsisten
t
Page6
2)
x
2
+y
3
=4
x
4
+y
6
=2
A) y=–3
2x+12,wherexisanyrealnumber
or{(x,y)|y=–3
2x+12,wherexisanyrealnumber}
B) x=–1,y=15
2;–1,15
2
C) x=0,y=12;(0,12)
D) inconsisten
t
3)
9x +y=8
–45x –5y =-
40
A) y=–9x+8
,
wherexisanyrealnumber
or{(x,y)|y=–9x+8,wherexisanyrealnumber}
B) x=–9y+8
,
whereyisanyrealnumber
or{(x,y)|x=–9y+8,whereyisanyrealnumber}
C) y=9x+8
,
wherexisanyrealnumber
or{(x,y)|y=9x+8,wherexisanyrealnumber}
D) inconsisten
t
5 SolveSystemsofThreeEquationsContainingThreeVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Verifythatthevaluesofthevariableslistedaresolutionsofthesystemofequations.
1)
x+y+z=0
x–y+3z=14
5x+y+z=–4
x=4,y=–3,z=–1
A) solution B) notasolution
2)
x–y+2z=1
4x+z=1
x+5y+z=6
x=0,y=1,z=1
A) solution B) notasolution
Page7
Solvethesystemofequations.
3)
x+5y+2z=-
4
5y+4z=7
z=3
A) x=–5
,
y=–1
,
z=3;(–5
,
–1
,
3) B) x= –5
,
y=3
,
z= –1;(–5
,
3
,
–1)
C) x=3
,
y=–1
,
z=–5;(3
,
–1
,
–5) D) inconsisten
t
4)
x–y+3z=-
2
3x+z=-
2
x+3y+z=-
14
A) x=0
,
y=–4
,
z=–2;(0
,
–4
,
–2) B) x= –2
,
y=0
,
z= –4;(–2
,
0
,
–4)
C) x=–2
,
y=–4
,
z=0;(–2
,
–4
,
0) D) inconsisten
t
5)
x–y+5z=-
3
5x+z=0
x+5y+z=15
A) x=0
,
y=3
,
z=0;(0
,
3
,
0) B) x=0
,
y=0
,
z=3;(0
,
0
,
3)
C) x=0
,
y=3
,
z=–3;(0
,
3
,
–3) D) inconsisten
t
6)
5x+4y+z=–29
2x–4y–z=1
5x+y+2z=–24
A) x=–4
,
y=–2
,
z=–1;(–4
,
–2
,
–1) B) x= –4
,
y= –1
,
z=–2;(–4
,
–1
,
–2)
C) x=–1
,
y=–2
,
z=–4;(–1
,
–2
,
–4) D) inconsisten
t
7)
7x+7y+z=1
x+8y+8z=8
9x+y+9z=9
A) x=0,y=0,z=1;(0,0,1) B) x=1,y= –1,z=1;(1,–1,1)
C) x=0,y=1,z=0;(0,1,0) D) x= –1,y=1,z=1;(–1,1,1)
8)
x+y+z=8
x–y+3z=6
5x+y+z=28
A) x=5
,
y=2
,
z=1;(5
,
2
,
1) B) x=1
,
y=5
,
z=2;(1
,
5
,
2)
C) x=1
,
y=2
,
z=5;(1
,
2
,
5) D) inconsisten
t
9)
x–y+z=1
x+y+z=–5
x+y–z=3
A) x=2
,
y=–3
,
z=–4;(2
,
–3
,
–4) B) x=2
,
y= –4
,
z= –3;(2
,
–4
,
–3)
C) x=–3
,
y=–4
,
z=2;(–3
,
–4
,
2) D) inconsisten
t
Page8
10)
x+y+z=-
1
x–y+4z=7
5x+y+z=-
9
A) x=–2
,
y=–1
,
z=2;(–2
,
–1
,
2) B) x=2
,
y= –2
,
z= –1;(2
,
–2
,
–1)
C) x=2
,
y=–1
,
z=–2;(2
,
–1
,
–2) D) inconsisten
t
11)
4x+4y+z=-
25
3x–4y–z=-
3
2x+y+2z=-
19
A) x=–4
,
y=–1
,
z=–5;(–4
,
–1
,
–5) B) x= –4
,
y= –5
,
z=–1;(–4
,
–5
,
–1)
C) x=–5
,
y=–1
,
z=–4;(–5
,
–1
,
–4) D) inconsisten
t
12)
x+y+z=7
x–y+2z=7
5x+y+z=11
A) x=1,y=2,z=4;(1,2,4) B) x=1,y=4,z=2;(1,4,2)
C) x=4,y=2,z=1;(4,2,1) D) x=4,y=1,z=2;(4,1,2)
13)
x–y+z=8
x+y+z=6
x+y–z=–12
A) x=–2,y=–1,z=9;(–2,–1,9) B) x=2,y= –1,z=9;(2,–1,9)
C) x=–2,y=–1,z=–9;(–2,–1,–9) D) x=2,y= –1,z= –9;(2,–1,–9)
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
Solvetheproblem.
14) Findrealnumbersa,b,andcsuchthatthegraphofthefunctiony=ax2+bx+ccontainsthepoints(1,1),
(2,4),and(–3,29).
15) Findrealnumbersa,b,andcsuchthatthegraphofthefunctiony=ax2+bx+ccontainsthepoints(1,2),
(2,11),and(–3,–14).
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
16) TheFamilyArtsCentercharges$23foradults,$15 forseniorcitizens,and$7 forchildrenunder12for
theirliveperformancesonSundayafternoon.ThispastSunday,thepaidrevenuewas$11,099for765
ticketssold.Therewere47morechildrenthanadults.Howmanychildrenattended?
A) 259children B) 212children C) 294 children D) 249 children
17) Ronattendsacocktailparty(withhisgraphingcalculatorinhispocket).Hewantstolimithisfoodintake
to122gprotein,118gfat,and159gcarbohydrate.Accordingtothehealthconscioushostess,the
marinatedmushroomcapshave3gprotein,5gfat,and9gcarbohydrate;thespicymeatballshave14g
protein,7gfat,and15gcarbohydrate;andthedeviledeggshave13gprotein,15gfat,and6g
carbohydrate.Howmanyofeachsnackcanheeattoobtainhisgoal?
A) 9mushrooms,4meatballs,3eggs B) 4 mushrooms,3 meatballs,9eggs
C) 3mushrooms,9meatballs,4eggs D) 10 mushrooms,5meatballs,4eggs
Page9
18) Aceramicsworkshopmakeswreaths,trees,andsleighsforsaleatChristmas.Awreathtakes3hoursto
prepare,2hourstopaint,and9hourstofire.Atreetakes16hourstoprepare,3hourstopaint,and4
hourstofire.Asleightakes4hourstoprepare,15hourstopaint,and7hourstofire.Iftheworkshophas
93hoursforpreparationtime,56hoursforpainting,and93hoursforfiring,howmanyofeachcanbe
made?
A) 7wreaths,4trees,2sleighs B) 4 wreaths,2 trees,7sleighs
C) 2wreaths,7trees,4sleighs D) 8 wreaths,5 trees,3sleighs
19) ThreeshrimpboatssupplytheshrimpwholesalersonHiltonHeadwithfreshcatch.TheAnnabelletakes
50%ofitscatchtoHudsonʹs,20%toCaptainJʹs,and30%toMainstreet.TheCurlyQtakes40%ofitscatch
toHudsonʹs,40%toCaptainJʹs,and20%toMainstreet.TheSloJoetakes30%ofitscatchtoHudsonʹs,40%
toCaptainJʹs,and30%toMainstreet.OneweekHudsonʹsreceived248.1poundsofshrimp,CaptainJʹs
received218.4pounds,andMainstreetreceived162.5pounds.Howmanypoundsofshrimpdideachboat
catch?
A) Annabelle166lbs,CurlyQ262lbs,SloJoe201 lbs
B) Annabelle262lbs,CurlyQ201lbs,SloJoe166 lbs
C) Annabelle201lbs,CurlyQ262lbs,SloJoe166 lbs
D) Annabelle201lbs,CurlyQ166lbs,SloJoe262 lbs
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
20) Toraisemoney,agroupofthreefriendsiseachtryingtosell100candles.Eachfriendhasapackage
containingthesamenumberoftapers,votives,andtealights.Thetaperssellfor$6.00each,thevotivessell
for$1.50each,andthetealightssellfor$0.75each.Mayasoldallofthecandlestoraise$431.25,Lorrinsold
allofthetapersandtealightstoraise$378.75,whileSarasoldallthevotives,allthetealights,andhalfof
thetaperstoraise$251.25.Howmanyofeachtypeofcandledideachpackagecontain?
21) Meishahas$25,000thatshewantstoinvest.Sheinvestsitinaccountspaying12%,7%,and6%simple
interest.Theaccountpaying12%isahigher–riskaccount,soshewantstheamountinthataccounttobe
halfoftheamountshehasintheaccountpaying6%simpleinterest.Ifherannualinterestis$1945,how
muchisinvestedateachrate?
22) Lexiewantstohaveanincomeof$9000peryearfrominvestments.Tothatendsheisgoingtoinvest
$90,000inthreedifferentaccounts.Theseaccountspay7%,10%,and14%simpleinterest.Ifshewantsto
have$10,000moreintheaccountpaying7%simpleinterestthanshehasintheaccountpaying14%simple
interest,howmuchshouldgointoeachaccount?
23) Craig,Jenni,andJadegotoastorehavingasaleonworkoutgear.Craigbuysthreepairsofsocks,two
T–shirts,andonepairofshortsfor$35.90.Jennibuysfourpairsofsocks,threeT–shirts,andthreepairsof
shortsfor$71.35.Jadebuysonepairofsocks,fourT–shirts,and2pairsofshortsfor$59.30.Whatisthe
priceofeachitem?
24) Ahealthshopownermadetrailmixcontainingdriedfruit,nuts,andcarobchips.Thedriedfruitsellsfor
$5.50perpound,thenutssellfor$7.50perpound,andthecarobchipssellfor$8.50perpound.Theshop
ownermixed50poundsofthetrailmixandsellsitfor$6.70perpound.Iftheamountofnutsisfive
poundsmorethantheamountofcarobships,howmuchofeachitemwasusedforthetrailmix?
Page10
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
25) AnapplicationofKirchoffʹsRulestothecircuitshownresultsinthefollowingsystemofequations:
I2+I3=I1
28+56–14I1–14I2=0
56–14I1–7I3=0
FindthecurrentsI1,I2,andI3.
28V56V
11Ω
7Ω 4Ω
3Ω 10Ω
A) I1=3.5,I2=2.5,andI3=1B)I
1=5.5,I2=4.5,andI3=1
C) I1=4.5,I2=3.5,andI3=1D)I
1=2.5,I2=1.5,andI3=1
6 IdentifyInconsistentSystemsofEquationsContainingThreeVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequations.Ifthesystemhasnosolution,saythatitisinconsistent.
1)
x+y+z=-
1
x–y+3z=-
5
2x+2y+2z=4
A) x=5
,
y=–2
,
z=–4;(5
,
–2
,
–4) B) x= –4
,
y= –2
,
z=5;(–4
,
–2
,
5)
C) x=–4
,
y=5
,
z=–2;(–4
,
5
,
–2) D) inconsisten
t
2)
x–y+4z=1
4x+z=0
–x+y–4z=-
4
A) x=0
,
y=–1
,
z=0;(0
,
–1
,
0) B) x=4
,
y= –1
,
z=0;(4
,
–1
,
0)
C) x=0
,
y=0
,
z=–1;(0
,
0
,
–1) D) inconsisten
t
Page11
7 ExpresstheSolutionsofaSystemofDependentEquationsContainingThreeVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequations.
1)
x+4y–z=3
x+5y–2z=5
3x+12y–3z=9
A) x=–3z–5,andy=z+2,wherezisanyrealnumber
or{(x,y,z)|x=–3z–5,andy=z+2,wherezisanyrealnumber}
B) x=z–2,andy=–3z–5,wherezisanyrealnumber
or{(x,y,z)|x=z–2,andy=–3z–5,wherezisanyrealnumber}
C) x=3z+5,andy=z–2,wherezisanyrealnumber
or{(x,y,z)|x=3z+5,andy=z–2,wherezisanyrealnumber}
D) inconsisten
t
2)
–x+y+2z=0
x+2y+z=6
–2x–y+z=-
6
A) x=z+2,andy=2–z,wherezisanyrealnumber
or{(x,y,z)|x=z+2,andy=2–z,wherezisanyrealnumber}
B) x=2–z,andy=z+2,wherezisanyrealnumber
or{(x,y,z)|x=2–z,andy=z+2,wherezisanyrealnumber}
C) x=z+2,andy=z–2,wherezisanyrealnumber
or{(x,y,z)|x=z+2,andy=z–2,wherezisanyrealnumber}
D) inconsisten
t
3)
2x–y+5z=-
7
x+y–2z=-
2
 x–y+4z=-
4
A) x=–3–z,andy=3z+1,wherezisanyrealnumber
or{(x,y,z)|x=–3–z,andy=3z+1,wherezisanyrealnumber}
B) x=3z+1,andy=z–3,wherezisanyrealnumber
or{(x,y,z)|x=3z+1,andy=z–3,wherezisanyrealnumber}
C) x=z+3,andy=3z+1,wherezisanyrealnumber
or{(x,y,z)|x=z+3,andy=3z+1,wherezisanyrealnumber}
D) inconsisten
t
Page12
4)
2x+4y–2z =0
3x+5y =1
A) x=2–5z,andy=3z–1,wherezisanyrealnumber
or{(x,y,z)|x=2–5z,andy=3z–1,wherezisanyrealnumber}
B) x=2+7z,andy=–3z–1,wherezisanyrealnumber
or{(x,y,z)|x=2+7z,andy=–3z–1,wherezisanyrealnumber}
C) x=–2–7z,andy=–3z–1,wherezisanyrealnumber
or{(x,y,z)|x=–2–7z,andy=–3z–1,wherezisanyrealnumber}
D) x=1–5z,andy=3z–1
2,wherezisanyrealnumber
or(x,y,z)|x=1–5z,andy=3z–1
2,wherezisanyrealnumber
12.2 SystemsofLinearEquations:Matrices
1 WritetheAugmentedMatrixofaSystemofLinearEquations
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Writetheaugmentedmatrixforthesystem.
1) 7x+2y=53
8x–2y=22
A) 7253
8–222 B) 53 2 7
22 8 –2C) 7853
2–222 D) 7222
–2853
2) –2x+4y=6
8y=48
A) –24 6
0848 B) –246
8480 C) 8048
–24 4 D) 64–2
48 0 8
3)
7x–y=0
–7x+y–14=0
A)
7–10
–7114
B)
7–10
–71–14
C)
7–70
–1114
D)
7–714
–110
4)
2.5x+0.3y=11.9
0.5x–0.9y=4.3
A)
2.5 0.3 11.9
0.5 –0.9 4.3
B)
2.5 11.9 0.3
0.5 4.3 –0.9
C)
2.5 0.5 11.9
–0.9 0.3 4.3
D)
11.9 0.3 2.5
4.3 –0.9 0.5
5)
1
2x+4
11y=–1
8
4
11x–1
2y=1
2
A)
1
2
 4
11
–1
8
4
11
–1
2
 1
2
B)
1
2
4
11
1
8
4
11
1
2
 1
2
C)
1
2
4
11
–1
8
4
11
1
2
–1
2
D)
1
2
4
11
–1
80
4
11
–1
2
1
20
6)
3x+6y+4z=73
7x+5y+9z=89
7x+7y–2z=96
A)
36 473
75 989
77–296
B)
36 4
75 9
77–2
C)
37 773
65 789
49–296
D)
73 463
89 957
96 –277
7)
–2x+4z=18
2y+7z=41
9x+3y+9z=63
A)
–20418
02741
93963
B)
–20918
02341
47963
C)
–24018
27041
93963
D)
–204
027
939
8)
9x+4y+5z=74
2x+5y+8z=59
2x+2y+8z=38
4x+2y+2z=2
A)
94574
25859
22838
4222
B)
9224
4522
5882
74 59 38 2
C)
9452
25838
22859
42274
D)
9222
4522
5882
74 59 38 4
Page14
9)
12x+2y–7z+w=–7
3y+z=–6
x–y–11z=–4
6x–6y+8z=1
A)
12 2 –71
–7
0310
–6
1–1–11 0 –4
6–6801
B)
12 2 –7–7
0 316
1–1–11 –4
6–681
C)
12019
23
–1–6
–71
–11 8
1 000
–7–6–41
D)
12 2 7 1 –7
0310
–6
1 1 11 0 –4
66801
2 WritetheSystemofEquationsfromtheAugmentedMatrix
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Writethesystemofequationsassociatedwiththeaugmentedmatrix.Donotsolve.
1) –53–4
63 3
A)
–5x+3y=–4
6x+3y=3 B)
–5x+3y=0
6x+3y=0 C)
3x–5y= –4
6x+3y=3 D)
–5x+3y= –4
3x+6y=3
2) 45 6
10 3 12
A)
4x+5y=6
10x+3y=12 B)
4x+5y= – 6
10x+3y=–12 C)
5x+4y=6
10x+3y=12 D)
4x+5y=6
3x+10y=12
3)
4723
4238
A)
4x+7y=23
4x+2y=38
B)
4x+4y=23
7x+2y=38
C)
23x+7y=–4
38x+2y=–4
D)
4x+38y=–7
7x+23y=–2
4)
1004
0108
0015
A)
x=4
y=8
z=5
B)
x= –4
y=–8
z=–5
C)
x=0
y=12
z=9
D)
x= –1
y=3
z=0
Page15
5)
2–4–3–7
–360–7
80–6–8
A)
2x–4y–3z=–7
–3x+6y=–7
8x–6z=–8
B)
2x–4y–3z=–7
–3x+6y–7z=0
8x–6y–8z=0
C)
2x–4y–3z=–7
–3x+6z=–7
8x–6y=–8
D)
2x–4y–3z=–7
–3x+6y=–7
8x–6y=–8
6)
766–2
8054
790 2
A)
7x +6y +6z =–2
8x +5z =4
7x +9y =2
B)
7x –6y +6z = –2
8x +5z =–4
7x +9y =–2
C)
7x +6y +6z = –2
8x +5z =4
7x +9z =2
7)
1000–8
0100–2
001010
00010
A)
x1=–8
x2=–2
x3=10
x4=0
B)
x1=8
x2=2
x3=–10
x4=0
C)
x1=0
x2=–10
x3=2
x4=8
D)
x1=–18
x2=–12
x3=0
x4=–12
Determinewhetherthesystemcorrespondingtothegivenaugmentedmatrixisconsistentorinconsistent.Ifitis
consistent,givethesolution.
8)
1007
010 7
000–8
A) consistent;x=7
,
y=7;(7
,
7) B) consistent;x= –7
,
y=–7;(–7
,
–7)
C) consistent;x=7
,
y=7
,
z=–8;(7
,
7
,
–8) D) inconsisten
t
9)
1000
010 0
000–1
A) consistent;x=0,y=0;(0,0) B) consistent;x=0,y=–1;(0,–1)
C) consistent;z=–1;(–9) D) inconsisten
t
Page16
10)
1559
0555
0013
A) consistent;x=4
,
y=–2
,
z=3;(4
,
–2
,
3) B) consistent;x=4
,
y=3
,
z=–2;(4
,
3
,
–2)
C) consistent;x=3
,
y=–2
,
z=4;(3
,
–2
,
4) D) inconsisten
t
11)
10–58
017 –6
000 0
A) consistent;x=8+5z,y=–6–7z,zanyrealnumber
or{(x,y,z)|x=8+5z,y=–6–7z,zanyrealnumber}
B) consistent;x=8–5z,y=–6+7z,zanyrealnumber
or{(x,y,z)|x=8–5z,y=–6+7z,zanyrealnumber}
C) consistent;x=8
,
y=–6
,
z=–5;(8
,
–6
,
–5)
D) inconsisten
t
12)
1001 2
0104 –4
001–70
0000 0
A) consistent;x1=2–x4
,
x2=–4–4x4
,
x3=7x4
,
x4anyrealnumber
or{(x,y,z)|x1=2–x4,x2=–4–4x4,x3=7x4,x4anyrealnumber}
B) consistent;x1=2+x4
,
x2=–4+4x4
,
x3= –7x4
,
x4anyrealnumber
or{(x,y,z)|x1=2+x4,x2=–4+4x4,x3=–7x4,x4anyrealnumber}
C) consistent;x1=4
,
x2=–7
,
x3=–2
,
x4= –7;(4
,
–7
,
–2
,
–7)
D) inconsisten
t
3 PerformRowOperationsonaMatrix
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Performtherowoperation(s)onthegivenaugmentedmatrix.
1) R1= 1
4r1
420 16
42
–4
A) 154
42–4B)
15 4
11
2
–1C) 15 4
570D) 15 16
42–4
2) R2=–1r1+r2
1210
15–3
A) 1210
03–13 B) 12 10
077C) –1–2–10
03–13 D) –1–2–10
15–3
Page17
3) R3=4r1+r3
–7–5–1–10
6–295
28 –6618
A)
–7–5–1–10
6–295
0–26 2–22
B)
–7–5–1–10
6–295
016 2–22
C)
–7–5–1–10
6–295
0–26 10 –22
D)
–7–5–1–10
6–295
016 10 –22
4) R2=–2r2+r1
246–8
1236
4671
A)
246–8
000–20
4671
B)
24 6 –8
0000
4671
C)
2 4 6 –8
–4–8–12 6
4671
D)
2 4 6 –8
–4–8–12 –20
4671
5) R2=–5r1+r2
4–415
–50 5–2
–12
–3–1
A)
4–41 5
–25 20 0 –27
–12
–3–1
B)
4–415
15 –20 10 23
–12
–3–1
C)
29 –4–24 15
–50 5
–2
–12
–3–1
D)
–25 20 0 –27
–505
–2
–12
–3–1
6) (a)R2=–3r1+r2
(b)R3=–3r1+r3
(c)R3=5r2+r3
1–3–5–2
3–5–45
3546
A)
1–3–5–2
0 4 11 11
0347467
B)
1–3–5–2
0–8–93
0–26 –26 –3
C)
1–3–5–2
0 4 11 11
0183023
D)
1–3–5–2
014194
0 84 114 32
7) (a)R2=–3r1+r2
(b)R3=3r1+r3
(c)R3=6r2+r3
1–3–52
3–525
–3–546
A)
1–3–52
0417
–1
01091 6
B)
1–3–52
0417
–1
0–98 –89 6
C)
1–3–52
0417
–1
0 28 121 6
D)
1–3–52
01417–1
00611
Page18
8) (a)R2=3r1+r2
(b)R3=–2r1+r3
(c)R3=4r2+r3
12–34
–3–58–10
20–14
A)
12–34
01–12
0014
B)
12–3–4
01–12
001–4
C)
12–34
011–2
0014
D)
12–3–4
01–12
0014
9) (a)R3=–4r1+r3
(b)R4=2r1+r4
11
–11 5
0–24
–30
40
–1–44
–110 5
–4
A)
11
–11 5
0–24
–30
0–43
–8–16
13
–27 6
B)
11
–115
0–24
–30
0–43
–8–16
–11 0 5
–4
C)
11
–115
0–24
–30
84
–5024
13
–276
D)
11
–11 5
0–24
–30
0–43
–80
13
–273
4 SolveaSystemofLinearEquationsUsingMatrices
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequationsusingmatrices(rowoperations).Ifthesystemhasnosolution,saythatitis
inconsistent.
1) 6x+6y=12
3x+2y=1
A) x=–3
,
y=5;(–3
,
5) B) x=5
,
y= –3;(5
,
–3)
C) x=–3
,
y=–5;(–3
,
–5) D) inconsisten
t
2) 9x–5y=-
3
–9x+5y=8
A) inconsisten
t
B) x=9
,
y=8;(9
,
8) C) x=-3
,
y=8;(–3
,
8) D) x=9
,
y=9;(9
,
9)
3)
x–y=5
x+y=3
A) x=4
,
y=–1;4
,
–1 B) x=1
,
y=2;1
,
2
C) x=8
,
y=–2;8
,
–2 D) inconsisten
t
Page19
4)
5x–4y=20
x+y=1
2
A) x=22
9,y=–35
18;22
9,–35
18 B) x=2,y=–3
2;2,–3
2
C) x=22,y=–43
2;22,–43
2D) inconsisten
t
5) 3x+5y =1
2x =-
6
A) x=–3
,
y=2;(–3
,
2) B) x=2
,
y= –3;(2
,
–3)
C) x=–3
,
y=–2;(–3
,
–2) D) inconsisten
t
6) 4x+y=3
5x+3y=-
5
A) x=2
,
y=–5;(2
,
–5) B) x= –5
,
y=2;(–5
,
2)
C) x=–5
,
y=–2;(–5
,
–2) D) inconsisten
t
7)
8x+5y–z=96
x–4y+6z=-
5
–6x+y+z=-
48
A) x=9
,
y=5
,
z=1;(9
,
5
,
1) B) x=9
,
y=1
,
z=5;(9
,
1
,
5)
C) x=–9
,
y=5
,
z=18;(–9
,
5
,
18) D) inconsisten
t
8)
7x–y–8z=-
16
–7x–7z=-
105
3y+z=11
A) x=7
,
y=1
,
z=8;(7
,
1
,
8) B) x=7
,
y=8
,
z=1;(7
,
8
,
1)
C) x=–7
,
y=1
,
z=14;(–7
,
1
,
14) D) inconsisten
t
9)
–5x+8y–z=26
x–7y+9z=-
22
5x+y+z=46
A) x=7
,
y=8
,
z=3;(7
,
8
,
3) B) x=7
,
y=3
,
z=8;(7
,
3
,
8)
C) x=–7
,
y=8
,
z=14;(–7
,
8
,
14) D) inconsisten
t
10)
8x–9y+5z=-
78
–24x+27y–15z=234
24x–27y+15z=-
234
A) x=9
8y–5
8z–39
4,yisanyrealnumber,zisanyrealnumber
or(x,y,z)|x=9
8y–5
8z–39
4,yisanyrealnumber,zisanyrealnumber
B) x=24
,
y=27
,
z=15;(24
,
27
,
15)
C) x=–2
,
y=8
,
z=2;(–2
,
8
,
2)
D) inconsisten
t
Page20
11)
x–y+3z=–1
5x+z=1
x+4y+z=17
A) x=0
,
y=4
,
z=1;(0
,
4
,
1) B) x=0
,
y=1
,
z=4;(0
,
1
,
4)
C) x=1
,
y=4
,
z=0;(1
,
4
,
0) D) x=1
,
y=0
,
z=4;(1
,
0
,
4)
12)
x+y+z=1
x–y+4z=–15
4x+y+z=10
A) x=3
,
y=2
,
z=–4;(3
,
2
,
–4) B) x=3
,
y= –4
,
z=2;(3
,
–4
,
2)
C) x=–4
,
y=2
,
z=3;(–4
,
2
,
3) D) x= –4
,
y=3
,
z=2;(–4
,
3
,
2)
13)
3x–2y+z=–7
x+y–2z=12
3x+y–z=10
A) x=1,y=3,z=–4;(1,3,–4) B) x=1,y= –3,z= –16;(1,–3,–16)
C) x=5,y=13
2,z=–3;5,13
2,–3 D) x=2,y=3,z= –7;(2,3,–7)
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
14)
–5x+2z=13
x+3y–2z=–15
4x+5y–z=–18
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
15)
x–y+2z+w=3
y+z=1
z–w=4
A) x=–8–4w,y=–3–w,z=4+w,wherewisanyrealnumber
B) inconsisten
t
C) x=–8
,
y=–3
,
z=4
,
w=0;(–8
,
–3
,
4
,
0)
D) x=–12
,
y=–4
,
z=5
,
w=1;(–12
,
–4
,
5
,
1)
16)
x+3y–2z–w=7
4x+y+z+2w=16
–3x–y–3z–2w=–13
x–y–3z–2w=–9
A) x=1
,
y=3
,
z=–1
,
w=5;(1
,
3
,
–1
,
5)
B) x=7
,
y=16
,
z=–13
,
w=–9;(7
,
16
,
–13
,
–9)
C) x=1+w,y=3–2w,z=–1+2w,wherewisanyrealnumber
D) x=0
,
y=5
,
z=–5
,
w=7;(0
,
5
,
–5
,
7)
Page21
17)
5x +y=6
3x –y+z–w=6
z+w=4
A) x=1+1
4w,y=1–5
4w,z=4–w,wherewisanyrealnumber
B) x=1–5
4w,y=1+1
4w,z=4–w,wherewisanyrealnumber
C) x=1–1
4w,y=1+5
4w,z=4–w,wherewisanyrealnumber
D) inconsisten
t
18)
3x+5y–2w=-13
2x+7z–w=-
1
4y+3z+3w=1
–x+2y+4z=-
5
A) x=1,y=–2,z=0,w=3;(1,–2,0,3) B) x=4
3,y=–13
20,z=0,w=5
2;4
3,–13
20,0,5
2
C) x=3
4,y=–2,z=0,w= 3
4;3
4,–2,0,3
4D) x=–1,y=–20
13,z=0,w=2
5;–1,–20
13,0,2
5
19)
x+y+z–w=6
2x–y+3z+4w =-
4
4x+2y–z–w=-13
–x–2y+4z+3w=12
A) x=–4,y=3,z=5,w=–2;(–4,3,5,–2) B) x=4,y= –3,z=–5,w=2;(4,–3,–5,2)
C) x=–1
4,y=1
3,z= 1
5,w=–1
2;–1
4,1
3,1
5,–1
2D) x=1
4,y=–1
3,z=–1
5,w=1
2;1
4,–1
3,–1
5,1
2
20)
3x+5y+2w=–12
2x+6z–w=–5
–2y+3z–3w=- 3
–x+2y+4z+w=–2
A) x=–1,y=–3,z=0,w=3;(–1,–3,0,3) B) x=1,y= –3,z=0,w=3;(1,–3,0,3)
C) x=–1,y=3,z=0,w=–3;(–1,3,0,–3) D) x=1,y=3,z=0,w=–3;(1,3,0,–3)
21)
x+y–z+w=–5
3x–y+3z–2w=7
–2x+2y+z–w=16
–x–2y–3z+3w=–22
A) x=–2,y=3,z=4,w=–2;(–2,3,4,–2)
B) x=–2,y=–3,z=5,w=1
2;–2,–3,5,1
2
C) x=2,y=–3,z=–4,w=–2;(2,–3,–4,–2)
D) x=1
2,y=–1
3,z=–1
4,w=–1
2;1
2,–1
3,–1
4,–1
2
Page22
Solvetheproblemusingmatrices.
22) Findthefunctionf(x)=ax3+bx2+cx+dforwhichf(0)=–2,f(1)=5,f(–1)=3,
f(2)=4.
A) f(x)=–10
3x3+6x2+13
3x–2 B) f(x)=10x3–18x2–13x+6
C) f(x)=8
3x3+4x2+5
3x–2 D) f(x)=–8x3+12x2+5x–6
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
23) Findrealnumbersa,b,andcsuchthatthegraphofthefunctiony=ax2+bx+ccontainsthepoints
(–2,–4),(1,–1),and(3,–19).
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
24) AnapplicationofKirchoffʹsRulestothecircuitshownresultsinthefollowingsystemofequations:
I2+I3=I1
28+56–14I1–14I2=0
56–14I1–7I3=0
FindthecurrentsI1,I2,andI3.
28V56V
11Ω
7Ω 4Ω
3Ω 10Ω
A) I1=3.5,I2=2.5,andI3=1B)I
1=5.5,I2=4.5,andI3=1
C) I1=4.5,I2=3.5,andI3=1D)I
1=2.5,I2=1.5,andI3=1
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
25) Melodyhas$45,000toinvestandwishestoreceiveanannualincomeof$4290fromthismoney.Shehas
choseninvestmentsthatpay5%,8%,and12%simpleinterest.Melodywantstohavetheamountinvested
at12%tobedoubletheamountinvestedat8%.Howmuchshouldsheinvestateachrate?
26) Acompanymanufacturesthreetypesofwoodenchairs:theKitui,theGoa,andtheSantaFe.Tomakea
Kituichairrequires1hourofcuttingtime,1.5hoursofassemblytime,and1houroffinishingtime.AGoa
chairrequires1.5hoursofcuttingtime,2.5hoursofassemblytimeand2hoursoffinishingtime.ASanta
Fechairrequires1.5hoursofcuttingtime,3hoursofassemblytime,and3hoursoffinishingtime.If41
hoursofcuttingtime,70hoursofassemblytime,and58hoursoffinishingtimewereusedoneweek,how
manyofeachtypeofchairwereproduced?
Page23
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
27) Thetablebelowshowsthenumberofbirdsforthreeselectedyearsafteranendangeredspeciesprotectio
n
programwasstarted.
x(Numberofyearsafter1980) 1  510
y(Numberofbirds) 40 160 445
Usethequadraticfunctiony=ax2+bx+ctomodelthedata.Solvethesystemoflinearequations
involvinga,b,andcusingmatrices.Findtheequationthatmodelsthedata.
A) y=3x2+12x+25 B) y=4x2+24x+20 C) y=5x2–12x+28 D) y=6x2–36x+21
28) Aceramicsworkshopmakeswreaths,trees,andsleighsforsaleatChristmas.Awreathtakes3hoursto
prepare,2hourstopaint,and10hourstofire.Atreetakes17hourstoprepare,3hourstopaint,and4
hourstofire.Asleightakes4hourstoprepare,16hourstopaint,and7hourstofire.Iftheworkshophas
125hoursforpreptime,95hoursforpainting,and128hoursforfiring,howmanyofeachcanbemade?
A) 8wreaths;5trees;4sleighs B) 5 wreaths;4 trees;8sleighs
C) 4wreaths;8trees;5sleighs D) 9 wreaths;6 trees;5sleighs
29) Therewereapproximately100vehiclessoldataparticulardealershiplastmonth.Thedealertrackssale
s
byagegroupformarketingpurposes.Thenumberof36–to59–year–oldbuyersandthenumberofbuyers
60andoldercombinedexceedsthenumberofbuyers35andyoungerby28.Ifthenumberofbuyersinthe
oldestgroupisdoubled,itis25lessthanthenumberofusersinthemiddlegroup.Findthenumberof
buyersineachofthethreeagegroups.
A) 36
,
35andyounger;51
,
36–59yearolds;13
,
60andolder
B) 38
,
35andyounger;48
,
36–59yearolds;14
,
60andolder
C) 13
,
35andyounger;51
,
36–59yearolds;36
,
60andolder
D) 30
,
35andyounger;53
,
36–59yearolds;17
,
60andolder
30) Ronattendsacocktailparty(withhisgraphingcalculatorinhispocket).Hewantstolimithisfoodintake
to157gprotein,137gfat,and177gcarbohydrate.Accordingtothehealthconscioushostess,the
marinatedmushroomcapshave3gprotein,5gfat,and9gcarbohydrate;thespicymeatballshave14g
protein,7gfat,and15gcarbohydrate;andthedeviledeggshave13gprotein,15gfat,and6g
carbohydrate.Howmanyofeachsnackcanheeattoobtainhisgoal?
A) 7mushrooms,6meatballs,4eggs B) 6 mushrooms,4 meatballs,7eggs
C) 4mushrooms,7meatballs,6eggs D) 8 mushrooms,7 meatballs,5eggs
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
31) Theperimeterofapictureframeis11feet.Ifthreetimestheheightisequaltoeighttimesthewidth,wha
t
arethedimensionsoftheframe?
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
32)
J
ennyreceives$1270peryearfromthreedifferentinvestmentstotaling$20,000.Oneoftheinvestments
pays6%,thesecondonepays8%,andthethirdonepays5%.Ifthemoneyinvestedat8%is$1500less
thantheamountinvestedat5%,howmuchmoneyhasJennyinvestedintheinvestmentthatpays6%?
A) $1500 B) $8500 C) $4500 D) $10,000
Page24
12.3 SystemsofLinearEquations:Determinants
1 Evaluate2by2Determinants
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Findthevalueofthedeterminant.
1) 27
92
A) –59 B) 67 C) 59 D) –4
2) 3–4
–78
A) –4 B) 52 C) 4 D) 44
3) 22
–13
A) 8 B) 4 C) –8D)7
4) 12 –7
–43
A) 8 B) 64 C) –8D)4
Solveforx.
5) 8x
25
=32
A) 4 B) 3 C) –4D)
–3
6)
59
–2x
=8
A) –2B)
–4C)2 D)
–5
2 UseCramerʹsRuletoSolveaSystemofTwoEquationsContainingTwoVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
SolvethesystemofequationsusingCramerʹsRuleifitisapplicable.IfCramerʹsRuleisnotapplicable,sayso.
1) 2x+5y=19
3x+y=-
4
A) x=–3
,
y=5;(–3
,
5) B) x=5
,
y= –3;(5
,
–3)
C) x=–5
,
y=–3;(–5
,
–3) D) x=3
,
y= –5;(3
,
–5)
2) 4x+4y=48
2x+5y=36
A) x=8
,
y=4;(8
,
4) B) x=4
,
y=8;(4
,
8)
C) x=–4
,
y=8;(–4
,
8) D) x= –8
,
y= –4;(–8
,
–4)
3) 2x+2y=26
2x–2y=-
6
A) x=5
,
y=8;(5
,
8) B) x=8
,
y=5;(8
,
5)
C) x=–8
,
y=5;(–8
,
5) D) x= –5
,
y= –8;(–5
,
–8)
Page25
4) 4x–7y=5
2x+5y=-
3
A) x=2
17,y=–11
17;2
17,–11
17 B) x=23
3,y=–11
3;23
3,–11
3
C) x=–2
17,y=11
17;–2
17,11
17 D) x=2
3,y=1
3;2
3,1
3
5)
2x–3y=6
6x–9y=24
A) notapplicable B) x=3
,
y=4;(3
,
4)
C) x=15
4,y=–5
2;15
4,–5
2D) x=6
,
y=24;(6
,
24)
6)
4x+2y=8
7
7x–7y=7
A) x=11
21,y=–10
21;11
21,–10
21 B) x=11
21,y=32
21;11
21,32
21
C) x=–11
21,y=–10
21;–11
21,–10
21 D) notapplicable
7)
x+2y=10
1
4x–y=–20
A) x=–20
,
y=15;–20
,
15 B) x= – 60
,
y=5;–60
,
5
C) x=100
3,y=85
3;100
3,85
3D) notapplicable
3 Evaluate3by3Determinants
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Findthevalueofthedeterminant.
1)
122
–115
215
A) 24 B) –16 C) –24 D) 22
2)
355
213
513
A) 30 B) 158 C) –30 D) –120
3)
–254
3–21
16–3
A) 130 B) 80 C) –90 D) –12
Page26
4)
300
765
393
A) –81 B) 189 C) 81 D) –76
5)
123
215
123
A) 0 B) 50 C) 1 D) –20
Solveforx.
6)
x–4–1
–220
–1–28
=10
A) 5 B) 2 C) 1 D) –2
7)
5–31
–2–2x
82–1
=28
A) 0 B) 1 C) –1D)2
8)
x14
1x–6
014
=7x
A) 0or1
4B) 0or–1
4C) 1
4D) –1
4
Solvetheproblem.
9) Theequationofthelinepassingthroughthedistinctpoints(x1,y1)and(x2,y2)isgivenby
xy1
x1y11
x2y21
=
0.Findtheequationofthelinepassingthroughthepoints(3,5)and(–1,4).
A) x–4y+17=0B)x+7y+17=0C)
–x+4y–17=0D)x+4y+17=0
10) Theequationofalinepassingthroughtwodistinctpoints(x1
,
y1)and(x2
,
y2)isgivenby
xy1
x2y21
x3y31
=0.Usethedeterminanttowriteanequationforthelinepassingthrough(9,7)and
(–3,–9).Expressthelineʹsequationinstandardform.
A) 16x–12y–60=0B)7x–3y–81 =0
C) –16x+12y–60=0D)
–9x+9y–21 =0
Page27
11) Determinantsareusedtoshowthatthreepointslieonthesameline(arecollinear).I
f
x1y11
x2y21
x3y31
=0,
thenthepoints(x1,y1),(x2,y2),and(x3,y3)arecollinear.Ifthedeterminantdoesnotequal0,thenthe
pointsarenotcollinear.Arethepoints(–4,–7),(0,8),and(–20,–67)collinear?
A) Yes B) No
12) Determinantsareusedtoshowthatthreepointslieonthesameline(arecollinear).I
f
x1y11
x2y21
x3y31
=0,
thenthepoints(x1,y1),(x2,y2),and(x3,y3)arecollinear.Ifthedeterminantdoesnotequal0,thenthe
pointsarenotcollinear.Arethepoints(–8,9),(0,–2),and(–24,34)collinear?
A) No B) Yes
13) Theareaofatrianglewithvertices(x1
,
y1),(x2
,
y2),and(x3
,
y3)is
Area=±1
2
x1y11
x2y21
x3y31
,
wherethesymbol±indicatesthattheappropriatesignshouldbechosentoyieldapositivearea.Usethis
formulatofindtheareaofatrianglewhoseverticesare(10,7),(3,–7),and(–10,–5).
A) 98 B) 196 C) 7 D) 14
4 UseCramerʹsRuletoSolveaSystemofThreeEquationsContainingThreeVariables
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
SolvethesystemofequationsusingCramerʹsRuleifitisapplicable.IfCramerʹsRuleisnotapplicable,sayso.
1)
9x+4y–z=22
x–8y–4z=-
41
–7x+y+z=-
11
A) x=3
,
y=1
,
z=9;(3
,
1
,
9) B) x=1
,
y=9
,
z=1;(1
,
9
,
1)
C) x=3
,
y=–1
,
z=–9;(3
,
–1
,
–9) D) x=4
,
y= –1
,
z=9;(4
,
–1
,
9)
2)
–5x–6y–7z=-
110
–9x+9y+8z=27
–9x–3y+7z=-
6
A) x=7
,
y=2
,
z=9;(7
,
2
,
9) B) x=2
,
y=9
,
z=2;(2
,
9
,
2)
C) x=7
,
y=–2
,
z=–9;(7
,
–2
,
–9) D) x=8
,
y=0
,
z=9;(8
,
0
,
9)
3)
–5x+9z=47
9x+6y–5z=41
5x–3y=7
A) x=5
,
y=6
,
z=8;(5
,
6
,
8) B) x=6
,
y=8
,
z=6;(6
,
8
,
6)
C) x=5
,
y=–6
,
z=–8;(5
,
–6
,
–8) D) x=6
,
y=4
,
z=8;(6
,
4
,
8)
Page28
4)
x–y+2z=-
1
3x+z=0
–x+y–2z=5
A) notapplicable B) x=0
,
y=1
,
z=0;(0
,
1
,
0)
C) x=2
,
y=1
,
z=0;(2
,
1
,
0) D) x=0
,
y=0
,
z=1;(0
,
0
,
1)
5 KnowPropertiesofDeterminants
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Usethepropertiesofdeterminantstofindthevalueoftheseconddeterminant,giventhevalueofthefirst.
1)
xy z
uv w
12–4
=43
12–4
uv w
xy z
=?
A) –43 B) 43 C) 0 D) Cannotdetermine
2)
xyz
uvw
1–2–4
=90
xy z
uv w
3–6–12
=?
A) 270 B) –90 C) –270 D) 90
3)
xy z
uvw
12 3
=40
uvw
36 9
xy z
=?
A) 120 B) –120 C) –40 D) 40
4)
xyz
uvw
1–3–1
=10
1–3–1
2u 2v 2w
x–1y+3z+1
=?
A) –20 B) –10 C) 20 D) 10
5)
xyz
uvw
1–2–4
=27
xy z–x
uvw–u
1–2–5
=?
A) 27 B) –27 C) 0 D) Cannotdetermine
6)
xy z
uvw
11 4
=–56
x–2y–2z–8
–2u–1–2v–1–2w–4
11 4
=?
A) 112 B) 56 C) –112 D) –56
7) Given
stu
vwx
428
=3,findthevalueof
32–s 16–t 64–u
vw x
42 8
.
A) 3 B) –24 C) 24 D) –3
Solvetheproblem.
8) Giventhat
xyz
abc
245
=3,findthevalueofthedeterminant
245
3a 3b 3c
x–2y–4z–5
.
A) –9B)9 C)0 D)6
Page29
12.4 MatrixAlgebra
1 FindtheSumandDifferenceofTwoMatrices
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Performtheindicatedoperation(s),wheneverpossible.
1)
LetA=[24]andB= –4
8.FindA+B.
A)
[–212]
B)
–2
12
C)
2–4
48
D) notdefined
2)
LetA=
3
–6
–4
andB=
–5
4
7
.FindA+B.
A)
–2
–2
3
B)
[–2–23]
C)
3–5
–64
–47
D)
2
3
4
3)
LetA=
–46
–56
–6–5
andB=
–32
21
–36
.FindA+B.
A)
–78
–37
–91
B)
–14
–75
–3–14
C)
–78
36
–9–1
D)
–76
–37
–91
4)
LetA=
–12
04
7–4
andB=
72
17 4
32
.FindA–B.
A)
–80
–17 0
4–6
B)
13
78
10 2
C)
10
70
4–2
D)
3–1
70
–46
5)
LetA=–91
25
andB=62
32 .FindA+B.
A)
–33
57
B)
34
37
C)
–3–7
–6–7
D)
12
Page30
6)
LetA=–10
43
andB=–14
31 .FindA–B.
A)
0–4
12
B)
–24
74
C)
04
–1–2
D)
[–1]
7)
LetA=2–4
–6–6,B=9–3
–4–6
andC=–57
–7–8.FindA+B–C.
A)
16 –14
–3–4
B)
60
–17 –20
C)
–2–8
58
D)
–12 6
–9–8
8) LetA=
7–48
–65
–1
06
–3
andB=
–2–6–1
–7–43
–3–9–5
. FindA–B.
A)
929
19
–4
315 2
B)
929
192
315–4
C)
5–10 7
–13 1 –8
–3–32
D)
5–10 7
–13 1 2
–3–3–8
9) LetA=
–467
3–512
7–11 14
andB=
610 –4
–56–8
311 7
.FindA–B.
A)
–10 –411
8–11 20
4–22 7
B)
216 3
–214
10 021
C)
–10 –43
–2–11 4
4–22 7
D)
10 4–11
–811 –20
–422 –7
10)
LetA=
222
40–1
–333
andB=
5–21
–301
24–3
.FindA+B.
A)
703
100
–170
B)
1–43
700
–170
C)
1–43
10
–2
170
D)
70 3
70–2
17 0
11)
LetA=
2–81
4–10 –2
536
andB=
–382
50–4
–65–3
.FindA–B.
A)
5–16 –1
–1–10 2
11 –29
B)
50
–1
–1–10 2
1–23
C)
516
–1
–1–10 2
11 2 9
D)
–103
9–10 –6
–183
Page31
2 FindScalarMultiplesofaMatrix
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Usethegivenmatricestocomputethegivenexpression.
1) LetA=–34
02 .Find2A.
A)
–68
04
B)
–68
02
C)
–64
02
D)
–16
24
2) LetB=–157–3.Find–4B.
A) 4–20 –28 12 B) 457–3C) –42028–12 D) –335–5
3) LetC=
2
–2
12
.Find1/2C.
A)
1
–1
6
B)
4
–4
24
C)
1
–2
12
D)
2
–1
12
4) LetA=23
26
andB=04
–16 .Find2A+B.
A)
410
318
B)
414
224
C)
410
112
D)
47
312
5) LetC=
1
–3
2
andD=
–1
3
–2
.FindC–4D.
A)
5
–15
10
B)
–3
9
4
C)
–5
15
–10
D)
5
–6
4
6) LetA=–12 andB=10 .Find2A+3B.
A) 14 B) –24 C) –14 D) 22
7) IfA=2–1
79
andB=5–3
47
,find–2A+4B.
A)
–24 –18
–30 –34
B)
16 –10
210
C)
74
11 13
D)
–3–6
35
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
8) IfA=7–5
–81
andB=–9–3
2–8,find–5A+4B.
Page32
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
9) LetA=
–2–46
44
–8
62
–3
andB=
–233
–9–9–9
5–1–8
.Find2A+4B.
A)
–12 4 24
–28 –28 –52
32 0 –38
B)
–6–515
–1–1–25
17 3 –14
C)
–4–19
–5–5–17
11 1 –11
D)
–4–511
–1–51
9–17 –11
3 FindtheProductofTwoMatrices
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Computetheproduct.
1)
–13
42
–20
–15
A)
–115
–10 10
B)
20
–410
C)
2–6
–37
D)
15 –1
10 –10
2)
13–1
40 3
30
–11
03
A)
00
12 9
B)
00
912
C)
3–30
009
D) notdefined
3)
0–31
5–10
12
01
1–1
A)
1–4
59
B)
15
–49
C)
010
0–1
00
D)
10 –51
5–10
–5–20
4)
–619
–2–3–8
5
–9
–2
A)
–57
33
B)
–619
–2–3–8
5–9–2
C)
–57 33
D) notdefined
Page33
5)
–825
8
0
–3
A) –79 B) 314 C) –64 0 –15 D)
–64
0
–15
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
6)
–2
1
–1
1–10
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
7)
26
–8
9–49
–3–46
9–5–4
829
A)
–16 –54 –84
9 2 151
B)
–16 9
–54 2
–84 151
C)
26–8
9–49
–3–49
9–5–4
889
D)
–6–24 –48
81 20 –36
72 –881
8)
–715
–296
5–69
513
–799
–795
A)
–77 47 13
–115 133 105
432 6
B)
–77 –115 4
47 –115 32
13 105 6
C)
–715
–296
5–69
513
–799
–795
D)
–35 1 15
14 81 54
–35 –54 45
9)
2–8
16
01
–32
1–1
61
A)
410 –24
12 –59
1–12
B)
–24 10 4
9–512
2–11
C)
9–14
–24 –51
210 12
D) notdefined
Page34
10)
3–21
04
–3
30
–22
A)
90
08
B)
9–63
–612–8
C)
9–6
–612
3–8
D) notdefined
11)
–13
12
0–24
1–32
A)
3–72
2–88
B) notdefined C)
32
–7–8
28
D)
0–612
1–64
12)
[172]
–66
–5
3–9–4
–4–9–1
A) 7–75 –35 B)
7
–75
–35
C)
1702
–66–5
3–9–4
–4–9–1
D)
–642
–10
3–63 –8
–4–63 –2
Performtheindicatedoperationsandsimplify.
13) LetA=3–4
–25
,B=5–28
10–3
,andC=
7–90
3–51
–162
.FindAB+BC.
A) 32 750
5–23 –37 B) 68 331
8–2–5C) 32 19 40
–15 31 –37 D) –10 –19 12
–15 31 –25
14)
LetA=
0–1
60
24
,B=
–40
11
56
,andC=–216
0–5–1.FindC(A–B).
A) –21 –11
–22 7 B) –4–10
–18 –3C) –18 –3
–4–10 D) –32 8
19 1
15)
LetA=
33
10
3–1
,B=
–41
03
–1–3
,andC=334
1–30.FindBC+6ℐ3.
A)
–5–15 –16
3–30
–66 2
B)
–11 –15 –16
3–90
–66
–4
C)
19 9 16
3150
612 10
D)
13 9 16
390
612 4
Page35
Solvetheproblem.
16) StateUniversityhasaCollegeofArts&Sciences,aCollegeofBusiness,andaCollegeofEngineering.The
percentageofstudentsineachcategoryaregivenbythefollowingmatrix.
Freshman Sophomore Junior Senior
Arts&Sciences
Business
Engineering
60% 50% 40% 70%
20% 40% 30% 10%
20% 10% 30% 20%
Thestudentpopulationisdistributedbyclassandageasgiveninthefollowingmatrix.
Female Male
Freshman
Sophomore
Junior
Senior
410 780
550 750
820 670
630 480
HowmanyfemalestudentsareintheCollegeofBusiness?HowmanymalestudentsareintheCollegeof
Arts&Sciences?
A) 611students;1447students B) 509 students;705students
C) 705students;528students D) 1290 students;611students
17) Thefinalgradeforanalgebracourseisdeterminedbygradesonthemidtermandfinalexam.Thegrades
forfourstudentsandtwopossiblegradingsystemsaremodeledbythefollowingmatrices.
Midterm Final
Student1
Student2
Student3
Student4
73 79
44 62
83 83
98 96
System
1
System
2
Midterm
Final
0.2 0.5
0.8 0.5
FindthefinalcoursescoreforStudent3forbothgradingSystem1andSystem2.
A) System1:83;System2:83 B) System1:58.1;System2:107.9
C) System1:77.8;System2:76 D) System1:39.8;System2:53
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
18) Acompanymanufacturesthreetypesofwoodenchairsattwodifferentlocations.Inoneweek,themain
locationproduces18Kituichairs,12Goachairs,and6SantaFechairswhilethesecondarylocation
produces10Kituichairs,3Goachairs,and5SantaFechairs.
(a)Finda2by3matrixrepresentingtheabovedata.
(b)IfeachKituichairrequires25board–feetofwood,aGoachairrequires29board–feetofwood,anda
SantaFerequires30board–feetofwood,finda3by1matrixrepresentingtheamountofmaterial.
(c)Multiplythe2by3matrixfoundinpartaandthe3by1matrixfoundinpartbtogeta2by1matrix
showingtheweekʹsusageofmaterialatbothlocations.
Page36
19) Thematrix922
435
representsoneweekʹsusageofwood(inboard–feet)attwolocationsofacompanythat
manufactureschairs.Duetodifferencesintransportationcosts,thefirstlocationpays$0.89perboard–foot
andthesecondlocationpays$0.94perboard–foot.
(a)Finda1by2matrixrepresentingthecostofthewood.
(b)Multiplythegivenmatrixandthematrixfoundinpartatodeterminethetotalcostofwoodforthat
week.
4 FindtheInverseofaMatrix
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Eachmatrixisnonsingular.Findtheinverseofthematrix.Besuretocheckyouranswer.
1)
53
32
A) 2–3
–35 B) 23
35 C)
1
2
–3
–31
5
D)
1
23
31
5
2)
10 1
–10
A) 0–1
110 B) 01
–110 C) 01
110 D) 0–1
–110
3)
–24
4–4
A)
1
2
1
2
1
2
1
4
B)
1
2
1
4
1
2
1
4
C)
–1
2
1
4
1
2
–1
4
D)
1
2
–1
2
–1
2
1
4
4)
–5–1
60
A)
01
6
–1–5
6
B)
01
6
–15
6
C)
0–1
6
1–5
6
D)
05
6
–1–1
6
5)
45
1–5
A)
1
5
1
5
1
25
–4
25
B)
1
5
–1
5
1
25
4
25
C)
–1
5
–1
5
–1
25
4
25
D)
4
25
1
5
1
25
–1
5
Page37
6)
6–4
–3–4
A)
1
9
–1
9
–1
12
–1
6
B)
1
9
1
9
1
12
–1
6
C)
–1
12
–1
6
1
9
–1
9
D)
–1
6
–1
9
–1
12
1
9
7)
05
13
A)
–3
51
1
50
B)
–3
5
–1
–1
50
C)
1
50
–3
51
D)
01
1
5
–3
5
8)
55
05
A)
1
5
–1
5
01
5
B)
1
5
1
5
01
5
C)
01
5
1
5
–1
5
D)
1
5
–1
5
01
5
9)
4–2
30
A)
01
3
–1
2
2
3
B)
0–1
3
1
2
2
3
C)
–1
2
2
3
01
3
D)
2
3
1
3
–1
20
10)
–5a
–7a
A)
a
2
–a
2
7
2
–5
2
B)
a
2
1
2
–7
2
a
2
C)
a
2
–7
2
a
2
5
2
D)
a
2
1
2
7
2
a
2
Page38
11)
2–10
–11
–2
10
–1
A)
1–12
–3–2–4
–1–11
B)
1–12
–3–24
–111
C)
1–22
3–2–4
–1–12
D)
1–12
–2–1–4
–1–11
12)
100
110
111
A)
100
–110
0–11
B)
100
111
0–11
C)
10–1
–110
0–11
D)
100
–1–10
011
13)
3–31
–22–1
–45
–2
A)
1–11
0–21
–2–30
B)
1–31
0–21
–2–30
C)
1–11
–2–30
0–21
D)
1–10
–2–30
0–2–1
14)
10 0
–11 0
08 1
A)
100
110
–8–81
B)
100
–110
008
C)
188
011
001
D)
100
8–10
8–11
15)
100
–110
111
A)
100
110
–2–11
B)
111
011
001
C)
1–11
01
–1
001
D)
–100
–1–10
–1–1–1
16)
111
211
223
A)
–110
4–1–1
–201
B)
–1–1–1
–2–1–1
–2–2–3
C)
11 1
1
211
1
2
 1
2
1
3
D)
1–1 1
1
211
1
2
 1
2
–1
3
Page39
17)
132
133
278
A)
–310–3
2–41
–110
B)
–1–3–2
–1–3–3
–2–7–8
C)
1 1
3
 1
2
11
3
1
3
1
2
1
7
1
8
D)
1–1
3
 1
2
1–1
3
1
3
1
7
1
2
1
8
18)
108
123
253
A)
9–40 16
–313 –5
–15–2
B)
112
025
833
C)
–1 0 –8
–1–2–3
–2–5–3
D)
–1–12
02
–5
823
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
Showthatthematrixhasnoinverse.
19)
4–6
–23
20)
2104
–3–11
–174
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Useagraphingutilitytofindtheinverse,ifitexists,ofthematrix.Roundanswerstotwodecimalplaces.
21)
–16 3 28
5–14 15
34 25 2
A)
–0.02 0.03 0.02
0.02 –0.04 0.02
0.02 0.02 0.01
B)
–0.01 0.02 0.01
0.02 –0.03 0.01
0.02 0.02 0.01
C)
–0.01 0.03 0.02
0.02 –0.03 0.01
0.02 0.02 0.01
D)
–0.02 0.03 0.02
0.02 –0.04 0.01
0.02 0.02 0.00
5 SolveaSystemofLinearEquationsUsinganInverseMatrix
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemusingtheinversematrixmethod.
1)
–2x–6y=-
2
2x–y=-
5
A) x=–2,y=1;(–2,1) B) x=1,y= –2;(1,–2)
C) x=2,y=–1;(2,–1) D) x= –1,y=2;(–1,2)
2)
x+3y=-
8
21x+6y=3
A) x=1,y=–3;(1,–3) B) x= –3,y=1;(–3,1)
C) x=–1,y=3;(–1,3) D) x=3,y= –1;(3,–1)
3)
–3x+9y=9
3x+2y=13
A) x=3,y=2;(3,2) B) x=2,y=3;(2,3)
C) x=–3,y=–2;(–3,–2) D) x= –2,y= –3;(–2,–3)
4)
–5x+3y=8
2x–4y=-
20
A) x=2,y=6;(2,6) B) x=6,y=2;(6,2)
C) x=–2,y=–6;(–2,–6) D) x= –6,y= –2;(–6,–2)
5)
bx+2y =10
bx+3y =7b≠0
A) x=16
b,y=–3;16
b,–3 B) x=–3,y=16
b;–3,16
b
C) x=–16
b,y=3;–16
b,3 D) x=–16
b,y=–3;–16
b,–3
6)
x+2y+3z =-
9
x+y+z=7
2x+2y+z=-
6
Theinverseof
123
111
221
is
–14–1
1–52
02–1
.
A) x=43
,
y=–56
,
z=20;(43
,
–56
,
20) B) x=16
,
y= –83
,
z=11;(16
,
–83
,
11)
C) x=–36
,
y=–14
,
z=–6;(–36
,
–14
,
–6) D) x=13
,
y=14
,
z=8;(13
,
14
,
8)
Page41
7)
x+2y+3z =-
2
x+y+z=-
8
x–2z =8
Theinverseof
123
111
10–2
is
–24–1
3–52
–12–1
.
A) x=–36
,
y=50
,
z=–22;(–36
,
50
,
–22) B) x= –28
,
y=48
,
z=–22;(–28
,
48
,
–22)
C) x=–2
,
y=0,z=0;(–2
,
0,0) D) x= –28
,
y= –30
,
z=–10;(–28
,
–30
,
–10)
8)
x+2y+3z =12
x+y+z=-
2
–x+y+2z =-
10
Theinverseof
123
111
–112
is
1–1–1
–352
2–3–1
.
A) x=24
,
y=–66
,
z=40;(24
,
–66
,
40) B) x= –2
,
y=8
,
z= –6;(–2
,
8
,
–6)
C) x=12
,
y=–8
,
z=20;(12
,
–8
,
20) D) x=0
,
y=6
,
z=8;(0
,
6
,
8)
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
9)
4x +2z =-
20
x–y–5z =5
–3x –2y –z=12
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
10)
2x +4y –5z =-
8
x+5y +2z =-
1
3x +3y +3z =15
A) x=5,y=–2,z=2;(5,–2,2) B) x=2,y=5,z=2;(2,5,2)
C) x=5,y=2,z=–2;(5,2,–2) D) x= –5,y= –2,z=–2;(–5,–2,–2)
Useagraphingutilitytosolvethesystemofequations.Roundanswerstotwodecimalplaces.
11)
25x+61y–12z=15
18x–12y+7z=-
3
3x+4y–z=12
A) x=4.56,y=–6.06,z=–22.55;(4.56,–6.06,–22.55)
B) x=-22.55,y=4.56,z=–6.06;(–22.55,4.56,–6.06)
C) x=4.56,y=–22.55,z=–6.06;(4.56,–22.55,–6.06)
D) x=–22.55,y=–6.06,z=4.56;(–22.55,–6.06,4.56)
Page42
Encodeordecodethegivenmessage,asrequested,numberingthelettersofthealphabet1through26intheirusual
order.
12) UsethecodingmatrixA=37
25
toencodethemessageLIFE.
A) 99 53
69 37 B) 78 62
54 43 C) 54 28
129 67 D) –3–5
33
13) UsethecodingmatrixA=–1–3
25
toencodethemessageCARE.
A) –6–33
11 61 B) –57 –16
96 27 C) 18 105
–7–4D) –1–8
–4–29
14) UsethecodingmatrixA=
10–2
123
111
toencodethemessageCOME_HERE.
A)
–23 –11 –5
72 29 56
31 13 28
B)
35 5
15 0 18
13 8 5
C)
19 27 –21
–14 –30 39
811 –13
D)
–7–21 3
28 69 44
13 33 26
15) UsethecodingmatrixA=1–4
–29
anditsinverseA–1=94
21
todecodethecryptogram–7–8
16 21
.
A) ABLE B) ACTS C) ARMS D) ALAS
16) UsethecodingmatrixA=21
53
anditsinverseA–1=3–1
–52
todecodethecryptogram96
25 17
.
A) BEAD B) CARE C) DARE D) CURB
17) UsethecodingmatrixA=
111
–112
123
anditsinverseA–1=
–1–11
52–3
–3–12
todecodethecryptogram
37 16 35
38 20 4
82 40 60
.
A) GOOD_LUCK B) STAY_CALM C) LOOK_DOWN D) HELP_THEM
12.5 PartialFractionDecompositio
n
1 DecomposeP/Q,WhereQHasOnlyNonrepeatedLinearFactors
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Tellwhetherthegivenrationalexpressionisproperorimproper.
1) x2–9x+20
(x2–7x+12)(x+4)
A) proper B) improper
2) x3–13x+42
x2–9x+20
A) improper B) proper
Page43
Tellwhetherthegivenrationalexpressionisproperorimproper.Ifimproper,rewriteitasthesumofapolynomial
andaproperrationalexpression.
3) x
9–x
A) improper;–1+9
9–xB) proper
C) improper;1+9
9–xD) improper;1–9
9–x
4) x–4
x2+6
A) proper B) improper; x–4
(x+6)(x–6)
C) improper; 4
x+6
+4
x–6D) improper; 4
x+6
–4
x–6
Writethepartialfractiondecompositionoftherationalexpression.
5) x
(x–5)(x–6)
A) –5
x–5
+6
x–6B) 5
x–5
+–6
x–6C) –6
x–5
+5
x–6D) –5
x–5
+–6
x–6
6) x
x2–5x+6
A) –2
x–2
+3
x–3B) 2
x–2
+–3
x–3C) –3
x–2
+2
x–3D) –2
x–2
+–3
x–3
7) x–13
(x–3)(x–5)
A) 5
x–3
+–4
x–5B) –4
x–3
+5
x–5C) 5
x–3
+4
x–5D) 4
x–3
+–5
x–5
8) 7x–37
(x+5)(x–4)
A) 8
x+5
–1
x–4B) 8
x+5
+1
x–4C) 1
x–4
–8
x+5D) 7
x+5
–37
x–4
9) 5x2–x–16
x(x+1)(x–1)
A) 16
x
+–5
x+1
+–6
x–1B) 16
x
+5
x+1
+–6
x–1C) 16
x
+–5
x+1
+6
x–1D) 16
x
+–6
x+1
+5
x–1
10) 12x2+162x+384
(x+8)(x+2)(x+11)
A) 8
x+8
+2
x+2
+2
x+11 B) –8
x+8
–2
x+2
–2
x+11
C) –8
x+8
+2
x+2
+2
x+11 D) 8
x+8
+2
x+2
–2
x+11
Page44
11) 2x–5
x2–5x–6
A) 1
x–6
+1
x+1B) 1
x–3
+1
x–2C) 9
x+2
+1
x–3D) 17
x+6
–3
x–1
12) 17x–95
x2–11x+30
A) 10
x–5
+7
x–6B) 10
x–5
+–7
x–6C) 11
x–5
+6
x–6D) 10
x+5
+7
x+6
13) 16x2–21x–27
x(x+3)(x–3)
A) 3
x
+10
x+3
+3
x–3B) 3
x
+11
x+3
+2
x–3C) 3
x
+9
x+3
+4
x–3D) x+10
x2+3
+3
x–3
2 DecomposeP/Q,WhereQHasRepeatedLinearFactors
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Writethepartialfractiondecompositionoftherationalexpression.
1) 4x2+13x+11
(x+2)(x+1)2
A) 1
x+2
+3
x+1
+2
(x+1)2B) –1
x+2
+3
x+1
+–2
(x+1)2
C) 1
x+2
+–3
x+1
+2
(x+1)2D) 2
x+2
+3
x+1
+–1
(x+1)2
2) x+3
x3–2x2+x
A) 3
x
+–3
x–1
+4
(x–1)2B) 3
x
+4
x–1
+–3
(x–1)2
C) 3
x
+–3
x–1
+7
(x–1)2D) –3
x
+3
x–1
+4
(x–1)2
3) 100–15x
x3–10x2+25x
A) 4
x
+–4
x–5
+5
(x–5)2B) 4
x
+5
x–5
+–4
(x–5)2
C) 4
x
+–4
x–5
+10
(x–5)2D) –4
x
+4
x–5
+5
(x–5)2
Page45
4) x+1
(x–2)2(x+4)
A)
1
12
x–2
+
1
2
(x–2)2
+
–1
12
x+4
B)
1
2
(x–2)2
+
–1
12
x+4
C)
–1
x–2
+
1
4x
(x–2)2
+
–1
4
x+4
D) 12
x–2
+2
(x–2)2
+–12
x+4
5) 7x3–2
x2(x+1)3
A) 6
x
–2
x2
–6
x+1
+3
(x+1)2
–9
(x+1)3B) 2
x2
–6
x+1
+3
(x+1)2
–9
(x+1)3
C) 6
x
–6
x+1
+3
(x+1)2
–9
(x+1)3D) 6
x
+2
x2
+6
x+1
–3
(x+1)2
+9
(x+1)3
6) 5x+9
(x–7)2
A) 5
x–7
+44
(x–7)2B) 5
x–7
+70
(x–7)2C) 5
x–7
+x+44
(x–7)2D) 1
x–7
+x+44
(x–7)2
7) 9x2–9x+9
(x–1)3
A) 9
x–1
+9
(x–1)2
+9
(x–1)3B) 9
x–1
+9
(x–1)2
C) 9
x–1
+x+9
(x–1)2
+x2+9
(x–1)3D) 9
x–1
–9
(x–1)2
+9
(x–1)3
3 DecomposeP/Q,WhereQHasaNonrepeatedIrreducibleQuadraticFactor
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Writethepartialfractiondecompositionoftherationalexpression.
1) 14x+1
(x–1)(x2+x+1)
A) 5
x–1
+–5x+4
x2+x+1
B) 5
x–1
+–5
x+1
+4
x–1
C) –5
x–1
+5x+4
x2+x+1
D) 5
x–1
+4x–5
x2+x+1
Page46
2) x2–111
x4–x2–72
A) 1
x+3
–1
x–3
+7
x2+8
B) 1
x+3
+1
x–3
–7
x2+8
C) 1
x+3
–1
x–3
–7
x2+8
D) 1
x+3
+1
x–3
+7
x2+8
3) 3x–2
x3–1
A)
1
3
x–1
+
–1
3x+7
3
(x2+x+1)
B) 3
(x–1)2
+1
(x–1)3
C) 3
x–1
+–3(x–7)
x2+x+1
D)
1
2
x–1
+
5
2
x+1
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
4) x2–56
x4+5x2–36
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
5) 13x+2
x3–1
A) 5
x–1
+–5x+3
x2+x+1
B) 5
x–1
+–5
x+1
+3
x–1
C) –5
x–1
+5x+3
x2+x+1
D) 5
x–1
+3x–5
x2+x+1
6) 6x2–2x–16
(x–4)(x2+2)
A) 4
x–4
+2x+6
x2+2
B) 4
x–4
+2
x2+2
C) 4
x–4
+2x–6
x2+2
D) 4
x–4
+2
x+2
+6
(x+2)2
7) 8x2+8x+34
x3+2x2+6x+12
A) 5
x+2
+3x+2
x2+6
B) 5
x+2
+3
x2+6
C) 5
x+6
+3x+2
x2+2
D) 5
x+2
+3
x+6
+2
(x+6)2
Page47
8) –8x–56
(x–3)2(x2+1)
A) 4
x–3
+–8
(x–3)2
+–4x–4
x2+1
B) 4
x–3
+–8
(x–3)2
+–4
x2+1
C) 4
x–3
+–12
(x–3)2
+–4x+4
x2+1
D) –12x+4
(x–3)2
+–4x–4
x2+1
4 DecomposeP/Q,WhereQHasaRepeatedIrreducibleQuadraticFactor
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Writethepartialfractiondecompositionoftherationalexpression.
1) 2x3+4x2
(x2+5)2
A) 2x+4
x2+5
+–10x–20
(x2+5)2B) 2x–4
x2+5
+–10x+20
(x2+5)2C) 2x+4
x2+5
+10x+20
(x2+5)2D) 2x+4
x2+5
+10x–20
(x2+5)2
2) x2+2x+1
(x2+4)2
A) 1
x2+4
+2x–3
(x2+4)2B) x+1
x2+4
+2x–3
(x2+4)2C) 1
x2+4
+–x–3
(x2+4)2D) –1
x2+4
+2x–3
(x2+4)2
3) 4x3+26x–4
(x2+6)2
A) 4x
x2+6
+2x–4
(x2+6)2B) 4x+1
x2+6
+2x–4
(x2+6)2C) 4x
x2+6
+–2x–4
(x2+6)2D) 4x
x2+6
+2x+4
(x2+6)2
4) 2x3+4x2+12x+12
(x2+4)3
A) 2x+4
(x2+4)2
+4x–4
(x2+4)3B) x+1
x2+4
+2x+4
(x2+4)2
+4x–4
(x2+4)3
C) 2x–4
(x2+4)2
+4x+4
(x2+4)3D) x
x2+4
+2x+4
(x2+4)2
+4x–4
(x2+4)3
12.6 SystemsofNonlinearEquations
1 SolveaSystemofNonlinearEquationsUsingSubstitution
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Thegraphoftwoequationsalongwiththepointsofintersectionaregiven.Substitutethepointsofintersection
intothesystemsofequations.Arethepointsofintersectionsolutionstothesystemofequations(Y/N)?
1)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
35
30
25
20
15
10
5
-5
(5, 26)
(-3, 10)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
35
30
25
20
15
10
5
-5
(5, 26)
(-3, 10)
x2=y–1
y=2x+16
A) Yes B) No
2)
x
–10–8-6-4-2 2 4 6 810
y
100
50
-50
(0.6, -3.8)
(-4.6, 37.8)
x
–10–8-6-4-2 2 4 6 810
y
100
50
-50
(0.6, -3.8)
(-4.6, 37.8)
2x2=y+5
y=–8x+1
A) No B) Yes
Page49
3)
x
-7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7
y
7
6
5
4
3
2
1
-1
-2
-3
-4
-5
-6
-7
(3, 4)
(-5, 0)
x
-7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7
y
7
6
5
4
3
2
1
-1
-2
-3
-4
-5
-6
-7
(3, 4)
(-5, 0)
x2+y2=25
2y+x=5
A) No B) Yes
4)
x
-7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7
y
7
6
5
4
3
2
1
-1
-2
-3
-4
-5
-6
-7 (4, –6)
(-4, 6)
x
-7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7
y
7
6
5
4
3
2
1
-1
-2
-3
-4
-5
-6
-7 (4, –6)
(-4, 6)
x2+y2=52
2y+3x=0
A) Yes B) No
Page50
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
Graphtheequationsofthesystem.Thensolvethesystemtofindthepointsofintersection.
5)
y=x2–4x+4
y=–x+8
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
6)
x2+y2=81
x2–y2=81
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page51
7)
x2+y2=81
y=x2–9
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
8)
y=x
y=6–x
x
510
y
10
5
x
510
y
10
5
Page52
9)
(x+4)2+(y–1)2=4
y2–2y–x–7=0
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solvethesystemofequationsusingsubstitution.
10)
x2+y2=13
x+y=5
A) x=3
,
y=2;x=2
,
y=3
or(3,2),(2,3)
B) x= –3
,
y=2;x=–2
,
y=3
or(–3,2),(–2,3)
C) x=3
,
y=–2;x=2
,
y=–3
or(3,–2),(2,–3)
D) x= –3
,
y= –2;x=–2
,
y=–3
or(–3,–2),(–2,–3)
11)
xy=20
x+y=9
A) x=5
,
y=4;x=4
,
y=5
or(5,4),(4,5)
B) x= –5
,
y=4;x=–4
,
y=5
or(–5,4),(–4,5)
C) x=5
,
y=–4;x=4
,
y=–5
or(5,–4),(4,–5)
D) x= –5
,
y= –4;x=–4
,
y=–5
or(–5,–4),(–4,–5)
12)
x2+y2=181
x–y=1
A) x=–9
,
y=–10;x=10
,
y=9
or(–9,–10),(10,9)
B) x=9
,
y= –10;x=10
,
y=–9
or(9,–10),(10,–9)
C) x=–9
,
y=10;x= –10
,
y=9
or(–9,10),(–10,9)
D) x=9
,
y=10;x=10
,
y=9
or(9,10),(10,9)
Page53
13)
y=x2–4x+4
x+y=8
A) x=4
,
y=4;x=–1
,
y=9
or(4,4),(–1,9)
B) x= –4
,
y=12;x=1
,
y=7
or(–4,12),(1,7)
C) x=2
,
y=6or(2
,
6) D) x=4
,
y=12;x=–1
,
y=9
or(4,12),(–1,9)
14)
y=–x2+3
x2+y2=5
A) x=2
,
y=–1;x=1
,
y=2;x=–1
,
y=2;x= –2
,
y= –1
or(2,–1),(1,2),(–1,2),(–2,–1)
B) x=1
,
y=2;x=–1
,
y=2
or(1,2),(–1,2)
C) x=2
,
y=–1;x=–2
,
y=–1
or(2,–1),(–2,–1)
D) x=1
,
y=4;x=4
,
y=19
or(1,4),(4,19)
15)
x2+y2=4
x+y=2
A) x=0,y=2;x=2,y=0
or(0,2),(2,0)
B) x=0,y=0;x=2,y=–2
or(0,0),(2,–2)
C) x=0,y=–2;x=–2,y=0
or(0,–2),(–2,0)
D) x=2,y= –2;x=–2,y=–2
or(2,–2),(–2,–2)
16)
xy=20
x+y=9
A) x=5,y=4;x=4,y=5
or(5,4),(4,5)
B) x=6,y=3;x=3,y=6
or(6,3),(3,6)
C) x=10,y=2;x=2,y=10
or(10,2),(2,10)
D) x=20,y=1;x=1,y=20
or(20,1),(1,20)
17)
x2+y2=169
x+y=17
A) x=12,y=5;x=5,y=12
or(12,5),(5,12)
B) x= –12,y=5;x=–5,y=12
or(–12,5),(–5,12)
C) x=12,y=–5;x=5,y=–12
or(12,–5),(5,–12)
D) x=–12,y= –5;x=–5,y=–12
or(–12,–5),(–5,–12)
Page54
18)
xy–x2=–20
x–2y=3
A) x=5,y=1;x=–8,y=–11
2
or(5,1),–8,–11
2
B) x=–5,y=–1;x=8,y=11
2
or(–5,–1),8,11
2
C) x=5,y=1;x=–11
2,y=–8
or(5,1),–11
2,–8
D) x=–5,y=–1;x=11
2,y=8
or(–5,–1),–11
2,8
19)
x2–y2=39
x–y=3
A) x=8,y=5or(8,5) B) x=8,y= –5or(8,–5)
C) x=–8,y=5or(–8,5) D) x= –8,y= –5or(–8,–5)
20)
y=6x2–5x
y=2x+3
A) x=3
2,y=6;x=–1
3,y=7
3
or3
2,6 ),–1
3,–7
3
B) x=1
3,y=11
3;x=–3
2,y=0
or1
3,11
3,–3
2,0
C) x=1
6,y=10
3;x=1,y=5
or1
6,10
3,(1,5)
D) x=–1
2,y=2;x=1,y=5
or–1
2,2 ,(1,5)
21)
lnx=3lny
3x=27y
A) x=33,y=3or(3 3,3)B)x=3,y=33or(3,33)
C) x=9,y=3or(9,3)D)x=3,y=9or(3,9)
22)
7x–y=–3
y=x2–5
A) x=8
,
y=59;x=–1
,
y=–4
or(8,59),(–1,–4)
B) x= –8
,
y=59;x=1
,
y=–4
or(–8,59),(1,–4)
C) x=8
,
y=69;x=–1
,
y=6
or(8,69),(–1,6)
D) x= –8
,
y=59;x=–1
,
y=–4
or(–8,59),(–1,–4)
Page55
23)
y=x+2
y2=8x
A) x=2
,
y=4or(2
,
4) B) x=2
,
y=4;x= –2
,
y=0
or(2,4),(–2,0)
C) x=2
,
y=4;x=2
,
y=–4
or(2,4),(2,–4)
D) x=2
,
y=4;x=2
,
y=–4;x=–2
,
y=0
or(2,4),(2,–4),(–2,0)
24)
xy=1
–10x–y=7
A) x=–1
2
,y=–2;x=–1
5,y=–5
or–1
2,–2 ,–1
5,–5
B) x=–2,y=–1
2;x=–5,y=–1
5
or–2,–1
2,–5,–1
5
C) x=2,y=–2;x=5
,
y=–5
or(2,–2),(5,–5)
D) x=–1
5
,y=–5or–1
5,–5
25)
5x2+4y2=36
y=x+3
A) x=0,y=3;x=–8
3,y=1
3
or0,3 ,–8
3,1
3
B) x=0,y=–3;x=–8
3,y=1
3
or0,–3 ,–8
3,1
3
C) x=0,y=3;x=8
3,y=17
3
or0,3 ,8
3,17
3
D) x=0,y=–3;x=8
3,y=17
3
or0,–3 ,8
3,17
3
26)
xy=40
x2+y2=89
A) x=8
,
y=–8;x=–8
,
y=–5;x=5
,
y=8;x= –5
,
y= –8
or(8,–8),(–8,–5),(5,8),(–5,–8)
B) x=8
,
y=5;x=–8
,
y=–5;x=8
,
y= –5;x= –8
,
y=5
or(8,5),(–8,–5),(8,–5),(–8,5)
C) x=8
,
y=5;x=5
,
y=8;x=8
,
y= –5;x=5
,
y= –8
or(8,5),(5,8),(8,–5),(5,–8)
D) x=–8
,
y=–5;x=–5
,
y=–8;x= –8
,
y=5;x= –5
,
y=8
or(–8,–5),(–5,–8),(–8,5),(–5,8)
Page56
27)
y=(x+5)2+1
2x–y+10=0
A) x=–4,y=2or(–4,2) B) x= –4,y=2;x=4,y=18
or(–4,2),(4,18)
C) x=0,y=10;x=0,y=26
or(0,10),(0,26)
D) x= –5,y=0or(–5,0)
28)
2y–x=5
x2+y2–25=0
A) x=–5
,
y=0;x=3
,
y=4
or(–5,0),(3,4)
B) x=5
,
y=0;x= –5
,
y=0;x=3
,
y=4
or(5,0),(–5,0),(3,4)
C) x=0,y=5
2;x=4,y=9
2
or0,5
2,4,9
2
D) x=0,y=5
2;x=0,y=–5
2;x=4,y=9
2
or0,5
2,0,–5
2,4,9
2
29)
y=x2–2x–6
y=–x2–8x+2
A) x=–4
,
y=18;x=1
,
y=–7
or(–4,18),(1,–7)
B) x=4
,
y=2;x= –1
,
y=–3
or(4,2),(–1,–3)
C) x=–4
,
y=18;x=0,y=–6
or(–4,18),(0,–6)
D) x=4
,
y=2;x=0,y=–6
or(4,2),(0,–6)
30)
x+y=–7
x2+y2=6y+43
A) x=–6
,
y=–1;x=–4
,
y=–3
or(–6,–1),(–4,–3)
B) x= –1
,
y= –6;x=–3
,
y=–4
or(–1,–6),(–3,–4)
C) x=–8
,
y=1;x=–10
,
y=3
or(–8,1),(–10,3)
D) x=1
,
y= –8;x=3
,
y=–10
or(1,–8),(3,–10)
2 SolveaSystemofNonlinearEquationsUsingElimination
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solveusingelimination.
1)
x2+y2=106
x2–y2=56
A) x=9
,
y=5;x=–9
,
y=5;x=9
,
y= –5;x= –9
,
y= –5
or(9,5),(–9,5),(9,–5),(–9,–5)
B) x=9
,
y=5;x=5
,
y=9;x=–9
,
y= –5;x= –5
,
y= –9
or(9,5),(5,–9),(–9,–5),(–5,–9)
C) x=9
,
y=–5;x=9
,
y=5or(9
,
–5),(9
,
5)
D) x=–9
,
y=–5;x=–5
,
y=–9or(–9
,
–5),(–5
,
–9)
Page57
2)
3x2–3y2=63
3x2+4y2=91
A) x=5
,
y=2;x=–5
,
y=2;x=5
,
y= –2;x= –5
,
y= –2
or(5,2),(–5,2),(5,–2),(–5,–2)
B) x=5
,
y=2;x=2
,
y=5;x=–5
,
y= –2;x= –2
,
y= –5
or(5,2),(2,5),(–5,–2),(–2,–5)
C) x=5
,
y=–2;x=5
,
y=2or(5
,
–2),(5
,
2)
D) x=–5
,
y=–2;x=–2
,
y=–5or(–5
,
–2),(–2
,
–5)
3)
x2+y2=16
x2–y2=16
A) x=4
,
y=0;x=–4
,
y=0or(4
,
0),(–4
,
0) B) x=4
,
y=4;x= –4
,
y=4or(4
,
4),(–4
,
4)
C) x=4
,
y=0;x=4
,
y=4or(4
,
0),(4
,
4) D) x= –4
,
y=0;x=–4
,
y=4or(–4
,
0),(–4
,
4)
4)
x2+y2=64
x2
64
+y2
9
=1
A) x=–8,y=0;x=8,y=0or(–8,0),(8,0) B) x=0,y= –8;x=0,y=8or(0,–8),(0,8)
C) x=0,y=–3;x=0,y=3or(0,–3),(0,3) D) Norealsolutionexists.
5)
3x2+2y2=89
x2–2y2=–21
A) x=17,y=19;x=–17,y=19;x=,17,y=–19;x=–17,y=–19
or(17,19),(–17,19),(17,–19),(–17,–19)
B) x=19,y=17;x=–19,y=17;x=,19,y=–17;x=–19,y=–17
or(17,19),(–17,19),(17,–19),(–17,–19)
C) x=17,y=19;x=,17,y=–19;
or(17
,19),(17,–19)
D) x=–17,y=19;x=–17,y=–19
or(–17,19),(–17,–19)
6)
2x2+y2=17
3x2–2y2=–6
A) x=2,y=3;x=2,y=–3;x=–2,y=3;x= –2,y= –3
or(2,3),(2,–3),(–2,3),(–2,–3)
B) x=1,y=3;x=1,y=–3;x=–1,y=3;x= –1,y= –3
or(1,3),(1,–3),(–2,3),(–2,–3)
C) x=2,y=–3;x=–2,y=3or(2,–3),(–2,3)
D) x=1,y=3;x=–1,y=–3or(1,3),(–1,–3)
Page58
7)
2x2+xy–y2=3
x2+2xy+y2=3
A) x=23
3,y=3
3;x=–23
3,y=–3
3
or23
3,3
3,–23
3,–3
3
B) x=23
3,y=–3
3;x=–23
3,y=3
3
or23
3,–3
3,–23
3,3
3
C) x=–2
3,y=1
3;x=23
3,y=–1
3
or–2
3,1
3,23
3,–1
3
D) x=–2
3,y=–1
3;x=23
3,y=1
3
or–2
3,–1
3,23
3,1
3
Useagraphingutilitytosolvethesystemofequations.Expressthesolutionroundedtotwodecimalplaces.
8)
3x3+y2=6
x4y=2
A) x=1.18,y=1.03;x=1.07,y=1.52;x= –0.91,y=2.88
or(1.18,1.03),(1.07,1.52),(–0.91,2.88)
B) x=1.99,y=0.13;x=1.04,y=1.70;x= –0.91,y=2.95
or(1.99,0.13),(1.04,1.70),(–0.91,2.95)
C) x=1.81,y=0.28;x=0.20,y=2.45;x= –0.20,y= –2.45
or(1.81,0.28),(0.20,2.45),(–0.20,–2.45)
D) Norealsolutionexists.
9)
x3+y2=2
x2y=4
A) x=–1.37,y=2.14or(–1.37,2.14) B) x=2.14,y=1.37or(2.14,1.37)
C) x=1.37,y=2.14or(1.37,2.14) D) x=2.14,y= –1.37or(2.14,–1.37)
10)
y=x–4/3
y=ex
A) x=0.64,y=1.89or(0.64,1.89) B) x=0.48,y=1.63or(0.48,1.63)
C) x=0.22,y=0.98or(0.22,0.98) D) x=1.14,y=0.81or(1.14,0.81)
11)
x2+y2=25
y=–lnx
A) x=4.76,y=–1.52;x=0.01,y=5.00
or(4.76,–1.52),(0.01,5.00)
B) x= –4.76,y=1.52;x=–0.01,y=5.00
or(–4.76,1.52),(–0.01,5.00)
C) x=5.12,y=–3.67;x=0.76,y=2.05
or(5.12,–3.67),(0.76,2.05)
D) x=5.12,y=3.67;x=–0.76,y=2.05
or(5.12,3.67),(–0.76,2.05)
Solvetheproblem.
12) Thesumofthesquaresoftwonumbersis68.Thesumofthetwonumbersis10.Findthetwonumbers.
A) 2and8B)2and8 or–8 and–2
C) –8and–2D)
–2 and8 or–8 and2
Page59
13) Thesumofthesquaresoftwonumbersis58.Thedifferenceofthetwonumbersis–10.Findthetwo
numbers.
A) –7and3or–3and7B)
–7 and3
C) –3and7D)3and7 or–7 and–3
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
14) Thedifferenceoftwonumbersis5andthedifferenceoftheirsquaresis55.Findthenumbers.
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
15) Arighttrianglehasanareaof16squareinches.Thesquareofthehypotenuseis80.Findthelengthsofthe
legsofthetriangle.Roundyouranswertothenearestinch.
A) 4in.and8in. B) 16in.and64 in. C) 2 in.and16 in. D) 8in.and4 in.
16) Theperimeterofarectangleis46inchesanditsareais130 squareinches.Whatareitsdimensions?
A) 10in.by13in. B) 9in.by14 in. C) 11 in.by12 in. D) 9in.by12 in.
17) Asystemfortrackingshipsindicatedthatashipliesonahyperbolicpathdescribedby5x2–y2=4.The
processisrepeatedandtheshipisfoundtolieonahyperbolicpathdescribedbyy2–2x2=8.Ifitis
knownthattheshipislocatedinthefirstquadrantofthecoordinatesystem,determineitsexactlocation.
A) (2
,
4) B) (–2
,
–4) C) (4
,
2) D) (–4
,
–2)
18) Findthedimensionsofarectanglewhoseperimeteris36 feetandwhoseareais56squarefeet.
A) 4ftby14ft B) 3ftby15 ft C) 5 ftby13 ft D) 3ftby13 ft
19) Theareaofagardenis5880squarefeet,andthelengthofitsdiagonalis119 feet.Findthedimensionsof
thegarden.
A) 56ftby105ft B) 8ftby735 ft C) 392 ftby15 ft D) 120 ftby49 ft
20) Theareaofarectangularpieceofcardboardshownis576 squareinches.Thecardboardisusedtomakean
openboxbycuttinga5–inchsquarefromeachcornerandturningupthesides.Iftheboxistohavea
volumeof780cubicinches,findthedimensionsofthecardboardthatmustbeused.
A) 16in.by36in. B) 21in.by41 in. C) 11 in.by31 in. D) 6in.by21 in.
21) Arectangularpieceoftinhasanareaof810 squareinches.Asquareof2 inchesiscutfromeachcorner,
andanopenboxismadebyturninguptheendsandsides.Ifthevolumeoftheboxis1148cubicinches,
whatweretheoriginaldimensionsofthepieceoftin?
A) 18in.by45in. B) 20in.by47 in. C) 16 in.by43 in. D) 14in.by39 in.
22) Thediagonalofthefloorofarectangularofficecubicleis2ftlongerthanthelengthofthecubicleand5ft
longerthantwicethewidth.Findthedimensionsofthecubicle.Roundtothenearesttenth,ifnecessary.
A) width=9.7ft,length=22.4ft B) width=4ft,length=11ft
C) width=2ft,length=9ft D) width=3.9ft,length=9.7ft
Page60
23) Ina1–milerace,thewinnercrossesthefinishline15 feetaheadofthesecond–placerunnerand34 feet
aheadofthethird–placerunner.Assumingthateachrunnermaintainsaconstantspeedthroughoutthe
race,byhowmanyfeetdoesthesecond–placerunnerbeatthethird–placerunner?(5280feetin1mile.)
A) 19.05ft B) –15.1 ft C) –19.12 ft D) 4.01 ft
24) Apersonatthetopofa600foottallbuildingdropsayellowball.Theheightoftheyellowballisgivenby
theequationh=–16t2+600wherehismeasuredinfeetandtisthenumberofsecondssincetheyellow
ballwasdropped.Asecondperson,inthesamebuildingbutonalowerfloorthatis440feetfromthe
ground,dropsawhiteball2secondsaftertheyellowballwasdropped.Theheightofthewhiteballis
givenbytheequationh=–16(t–2)2+440wherehismeasuredinfeetandtisthenumberofseconds
sincetheyellowballwasdropped.Findthetimethattheballsarethesamedistanceabovethegroundand
findthisdistance.
A) 3.5sec;404ft B) 2.5sec;500 ft C) 3 sec;456 ft D) 4sec;344 ft
Page61
12.7 SystemsofInequalities
1 GraphanInequality
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Graphtheinequality.
1) x>–7
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page62
2) y≤1
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page63
3) 2x+y≤–6
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
B)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
C)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
D)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
Page64
4) x+5y≥2
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
B)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
C)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
D)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
Page65
5) y≥x–4
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
6) y+4
<
x
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page67
7) y≤5x+1
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
8) –3x–5y≤15
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page69
9) 2x+3y≤6
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page70
10) –3x–5y≤–15
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page71
11) x–y>–5
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page72
12) x+y
<
–3
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page73
13) x–y
<
–5
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page74
14) x2+y2≤36
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page75
15) x2+y2>49
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
16) y>x2–2
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page77
17) y≤x2+6
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page78
18) xy≤6
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page79
2 GraphaSystemofInequalities
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Graphthesystemofinequalities.
1) y>5
x≥2
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page80
2) 2x+y>4
2x+y<1
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
A) Nosolution
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
B)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
C)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
D)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
Page81
3) –2x+y
<
8
–2x+y>1
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
A)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
B)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
C)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
D) Nosolution
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Page82
4) 2x–y≤–8
x+4y≥–16
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
A)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
B)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
C)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
D)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Page83
5) y
<
–x+3
y>3x–3
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
–20 –10 10 20
y
20
10
-10
-20
x
–20 –10 10 20
y
20
10
-10
-20
D)
x
–20 –10 10 20
y
20
10
-10
-20
x
–20 –10 10 20
y
20
10
-10
-20
6) x+2y≥2
x–y≤0
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
7) –x+3y
<
9
x≥–1
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page86
8) y
<
x+1
4x+10y>10
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page87
9) x+5y≤5
x+5y≥0
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D) Nosolution
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
10) 2x+y≥2
2x+y≥0
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D) Nosolution
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page89
11) 2x+3y≤6
x–y≤3
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page90
12) 4x+3y≥12
x≥y
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
B)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
C)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
D)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
Page91
13) 2x+3y≥6
x–y≤3
y≤2
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
A)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
B)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
C)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
D)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
Page92
14) 2x+3y≥6
x–y≥3
y≤2
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
A)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
B)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
C)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
D)
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
x
-8 -6 -4 -2 2 4 6 8
y
8
6
4
2
-2
-4
-6
-8
Page93
15) –x+2y≤–6
3x+2y>–18
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
A)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
B)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
C)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
D)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Page94
16) x2+y2≤49
10x+6y≤60
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page95
17) y≥x2
x+y>3
x
y
x
y
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-12 -8 -4 4 8 12
y
12
8
4
-4
-8
-12
x
-12 -8 -4 4 8 12
y
12
8
4
-4
-8
-12
D)
x
-12 -8 -4 4 8 12
y
12
8
4
-4
-8
-12
x
-12 -8 -4 4 8 12
y
12
8
4
-4
-8
-12
18) x2+y≤4
x2–y≤1
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
A)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
B)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
C)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
D)
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
x
-5 -4 -3 -2 -1 1 2 3 4 5
y
5
4
3
2
1
-1
-2
-3
-4
-5
19) y>x2
3x+4y≤12
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page98
20) y>x2
8x+2y≤16
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page99
21) x2+y2≤36
–8x+3y≤–24
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page100
22) x2+y2≤36
y–x2>0
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
D)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Page101
23) x2+y2≤16
x+y>1
x
–10–8-6-4-2 2 4 6 810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
x
–10–8-6-4-2 2 4 6 810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
A)
x
–10–8–6–4–2 246810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
x
–10–8–6–4–2 246810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
B)
x
–10–8-6-4-2 2 4 6 810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
x
–10–8-6-4-2 2 4 6 810
y
12
10
8
6
4
2
-2
-4
-6
-8
-10
-12
C)
x
–10–8-6-4-2 2 4 6 8
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 8
y
10
8
6
4
2
-2
-4
-6
-8
-10
D)
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8-6-4-2 2 4 6 810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Page102
24) xy
<
9
y≤x2–1
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
B)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
C)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
D)
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
Page103
25) x2+y2≤64
x2+y2≥1
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
A)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
B) nosolution
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
C)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
D)
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
x
–8–6–4–2 2468
y
8
6
4
2
-2
-4
-6
-8
Page104
26) 2x+3y≥6
x–y≥3
y≤2
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page105
27) 2x+3y≥6
x–y≤3
x≥1
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page106
28) 2x+3y≤6
x–y≤3
x≥1
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page107
29) 2x+3y≤6
x–y≥3
x≥1
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
A)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
B)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
C)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
D)
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
x
-6 -4 -2 2 4 6
y
6
4
2
-2
-4
-6
Page108
30) y–x≤5
x+y≥3
y–3x≥–1
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
A)
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
B)
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
C)
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
D)
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
x
–10–8–6–4–2 246810
y
10
8
6
4
2
-2
-4
-6
-8
-10
Graphthesystemoflinearinequalities.Tellwhetherthegraphisboundedorunbounded,andlabelthecorner
points.
31)
x≥0
y≥0
x+y≤9
x+y≥5
Page109
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A) bounded;
cornerpoints(9,0),(0,9),(0,5),(5,0)
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
B) unbounded;
cornerpoints(0,0),(0,5),(5,0)
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
C) unbounded;
cornerpoints(9,0),(0,9)
x
y
12
-12
(0, 9)
(9, 0)
x
y
12
-12
(0, 9)
(9, 0)
D) nosolution
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
x
y
12
-12
(0, 9)
(9, 0)
(5, 0)
(0, 5)
Page110
32)
x≥0
y≥0
x+y≥2
x+2y≥4
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A) unbounded;cornerpoints(0,2),(4
,
0)
x
-5 5 10
y
10
5
-5
-10
(0, 2) (4, 0)
x
-5 5 10
y
10
5
-5
-10
(0, 2) (4, 0)
B) bounded;cornerpoints(0,0),(0,2),(2
,
0)
x
-10 -5 5 10
y
10
5
-5
-10
(0, 2)
(2, 0)
(0, 0)
x
-10 -5 5 10
y
10
5
-5
-10
(0, 2)
(2, 0)
(0, 0)
C) bounded;cornerpoints(2
,
0),(0,2),(4
,
0)
x
-10 -5 5 10
y
10
5
-5
-10
(2, 0)
(0, 2)
(4, 0)
x
-10 -5 5 10
y
10
5
-5
-10
(2, 0)
(0, 2)
(4, 0)
D) unbounded;cornerpoints(0,2),(2
,
0)
x
-10 -5 5 10
y
10
5
-5
-10
(0, 2)
(2, 0)
x
-10 -5 5 10
y
10
5
-5
-10
(0, 2)
(2, 0)
Page111
Graphtheregionindicatedbygraphingthesystemofinequalities.Labelallpointsofintersection.
33)
y≥x2–8
y≤–x2
x
-10 -5 5 10
y
10
5
-5
-10
x
-10 -5 5 10
y
10
5
-5
-10
A) O(0,0),A(0,–8)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
B) O(0,0),A(0,–8)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
C) O(0,0),A(0,–8)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
D) O(0,0),A(0,–8)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
x
-10 -5 5 10
y
10
5
-5
-10
O
A
(-2, –4) (2, –4)
Page112
Writeasystemoflinearinequalitiesthathasthegivengraph.
34)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
y≥0
x≥0
x≤4
y+x≤8
B)
y≥0
x≥0
x≤8
y+x≤4
C)
x≤4
y+x≤8
D)
y≥0
x≥0
x≤4
y+x≥8
35)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
y≥0
x≥0
x≤8
y≤8
x+y≥2
B)
y≥0
x≥0
y≤8
x+y≥2
C)
y≥0
x≥0
x≤8
x+y≥2
D)
x≤8
y≤8
x+y≥2
Page113
36)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
x≥0
y≥2
y≤x
y+x≤9
B)
y≥0
x≥0
y≤2
y≤x
y+x≤9
C)
y≥2
y≥x
y+x≤9
D)
y≥0
x≥0
y≤2
y+x≤9
37)
x
-10 10
y
10
-10
x
-10 10
y
10
-10
A)
y≥0
y≤9
y≤x–3
y≥3–x
B)
x≥0
y≥0
y≤9
y≤x–3
y≤3–x
C)
x≥0
y≤9
y≤x–3
y≥3–x
D)
y≥0
x≤9
y≤x–3
y≥3–x
Page114
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
Solvetheproblem.
38) Acoffeestorehasavailable75poundsofAgradecoffeeand120poundsofBgradecoffee.Thesewillbe
blendedinto1poundpackagesasfollow:aneconomyblendthatcontains4ouncesofAgradecoffeeand
12ouncesofBgradecoffeeandasuperiorblendthatcontains8ouncesofAgradecoffeeand8ouncesof
Bgradecoffee.Usingxtodenotethenumberofpackagesoftheeconomyblendandytodenotethe
numberofpackagesofthesuperiorblend,writeasystemoflinearinequalitiesthatdescribesthepossible
numberofpackagesofeachblend.Graphthesystemandlabelthecornerpoints.
x
y
x
y
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
39) Apersonwithnomorethan$1000toinvestplanstoplacethemoneyintwoinvestments,
telecommunicationsandpharmaceuticals.Thetelecommunicationsinvestmentistobenomorethan2
timesthepharmaceuticalsinvestment.Writeasystemofinequalitiestodescribethesituation.Let
x=amounttobeinvestedintelecommunicationsandy=amounttobeinvestedinpharmaceuticals.
A) x+y≤1000
x≤2y
x≥0
y≥0
B) x+y=1000
x≤2y
x≥0
y≥0
C) x+y=1000
y≥2x
x≥0
y≥0
D) x+y≤1000
2x≤y
x≥0
y≥0
40) Amanisplantingasectionofgardenwithtomatoesandcucumbers.Theavailableareaofthesectionis
140squarefeet.Hewantstheareaplantedwithtomatoestobemorethan25%oftheareaplantedwith
cucumbers.Writeasystemofinequalitiestodescribethesituation.Letx=amounttobeplantedin
tomatoesandy=amounttobeplantedincucumbers.
A) x+y≤140
x>0.25y
x≥0
y≥0
B) x+y=140
x≥0.25y
x≥0
y≥0
C) x+y≤140
x>25y
x≥0
y≥0
D) x+y≤140
x<0.25y
x≥0
y≥0
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12.8 LinearProgramming
1 SetupaLinearProgrammingProblem
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Setupthelinearprogrammingproblem.
1) Asteelcompanyproducestwotypesofmachinedies,partAandpartB.Thecompanymakesa$2.00
profitoneachpartAthatitproducesanda$5.00profitoneachpartBthatitproduces.Letx=thenumber
ofpartAproducedinaweekandy=thenumberofpartBproducedinaweek.Writetheobjective
functionthatdescribesthetotalweeklyprofit.
A) z=2x+5y B) z=5x+2y
C) z=7(x+y) D) z=2(x–5)+5(y–2)
2) Adietitianneedstopurchasefoodforpatients.Shecanpurchaseanounceofchickenfor$0.25 andan
ounceofpotatoesfor$0.03.Letx=thenumberofouncesofchickenandy=thenumberofouncesof
potatoespurchasedperpatient.Writetheobjectivefunctionthatdescribesthetotalcostperpatientper
meal.
A) z=0.25x+0.03y B) z=0.03x+0.25y C) z=25x+3y D) z=3y+25y
3) Asteelcompanyproducestwotypesofmachinedies,partAandpartBandisboundbythefollowing
constraints:
·PartArequires1hourofcastingtimeand10hoursoffiringtime.
·PartBrequires4hoursofcastingtimeand3hoursoffiringtime.
·Themaximumnumberofhoursperweekavailableforcastingandfiringare100and70,respectively.
·Thecosttothecompanyis$0.75perpartAand$3.00perpartB.Totalweeklycostscannotexceed
$45.00.
Letx=thenumberofpartAproducedinaweekandy=thenumberofpartBproducedinaweek.Write
asystemofthreeinequalitiesthatdescribestheseconstraints.
A)
x+4y ≤100
10x +3y ≤70
0.75x +3y ≤45
B)
x+10y ≤100
4x +3y ≤70
0.75x +3y ≤45
C)
x+10y ≥100
4x +3y ≥70
0.75x +3y ≤45
D)
x+4y ≤100
10x +3y ≤70
3x +0.75y ≤45
4) Adietitianneedstopurchasefoodforpatients.Shecanpurchaseanounceofchickenfor$0.25andan
ounceofpotatoesfor$0.02.Thedieticianisboundbythefollowingconstraints.
·Eachounceofchickencontains13gramsofproteinand24gramsofcarbohydrates.
·Eachounceofpotatoescontains5gramsofproteinand35gramsofcarbohydrates.
·Theminimumdailyrequirementsforthepatientsunderthedietitianʹscareare45gramsofproteinand
58gramsofcarbohydrates.
Letx=thenumberofouncesofchickenandy=thenumberofouncesofpotatoespurchasedperpatient.
Writeasystemofinequalitiesthatdescribestheseconstraints.
A)
13x +5y ≥45
24x +35y ≥58
B)
13x +24y ≥45
5x +35y ≥58
C)
13x +5y ≥58
24x +35y ≥45
D)
13x +24x ≥45
5y +35y ≥58
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5) Mrs.Whitewantstocrochethatsandafghansforachurchfundraisingbazaar.Sheneeds8hourstomake
ahatand2hourstomakeanafghan,andshehasnomorethan58hoursavailable.Shehasmaterialforno
morethan14items,andshewantstomakeatleasttwoafghans.Letx=thenumberofhatsshemakesand
y=thenumberofafghansshemakes.Writeasystemofinequalitiesthatdescribestheseconstraints.
A) 8x+2y≤58
x+y≤14
y≥2
B) 8x+2y≤58
x+y≤14
x≥2
C) 2x+8y≤58
x+y≤14
x≤2
D) 8x+2y≥58
x+y≤14
y≥2
6) Anofficemanagerisbuyingusedfilingcabinets.Smallfilecabinetscost$5 eachandlargefilecabinetscos
t
$12each,andthemanagercannotspendmorethan$102onfilecabinets.Asmallcabinettakesup6square
feetoffloorspaceandalargecabinettakesup9squarefeet,andtheofficehasnomorethan90squarefeet
offloorspaceavailableforfilecabinets.Themanagermustbuyatleast6filecabinetsinordertogetfree
delivery.Letx=thenumberofsmallfilecabinetsboughtandy=thenumberoflargefilecabinetsbought.
Writeasystemofinequalitiesthatdescribestheseconstraints.
A) 5x+12y≤102
6x+9y≤90
x+y≥6
B) 5x+12y≤102
9x+6y≤90
x≥6
C) 5x+12y≤102
6x+9y≤90
x+y≤6
D) 5x+12y≤102
6x+9y≤90
y≥6
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
7) TheJillsonʹshaveupto$75,000toinvest.Theydecidethattheywanttohaveatleast$40,000investedin
stablebondsyielding6%andthatnomorethan$20,000shouldbeinvestedinmorevolatilebonds
yielding12%.
(a)Usingxtodenotetheamountofmoneyinvestedinthestablebondsandytheamountinvestedinthe
morevolatilebonds,writeasystemoflinearinequalitiesthatdescribesthepossibleamountsofeach
investment.
(b)Graphthesystemandlabelthecornerpoints.
x
y
x
y
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8) Charlenebaby–sitsfor$4perhour.Shealsoworksasatutorfor$7perhour.Becauseofschool,her
parentsonlyallowhertowork13hoursperweek.HowmanyhourscanCharlenetutorandbaby–sitand
stillmakeatleast$50perweek?
(a)Letx=hoursspentbaby–sittingandlety=hoursspenttutoring.Writeasystemofinequalitiesforthis
situation.
(b)Graphthesolutionset.
x
4 8 12 16 20
y
16
12
8
4
x
4 8 12 16 20
y
16
12
8
4
9) EricʹsCarpentrymanufacturestwotypesofbookshelvesthatare4feettalland3feetwide,abasicmodel
andadeluxemodel.Eachbasicbookshelfrequires1.5hoursforassemblyand1hourforfinishing;each
deluxemodelrequires2.5hoursforassemblyand1hourforfinishing.Twoassemblersandonefinisherar
e
employedbythecompany,andeachworks40hoursperweek.
(a)Usingxtodenotethenumberofbasicbookcasesandytodenotethenumberofdeluxebookcases,
writeasystemoflinearinequalitiesthatdescribesthepossiblenumberofeachmodelofbookcasethatcan
bemanufacturedinaweek.
(b)Graphthesystemandlabelthecornerpoints.
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
10) Theliquidportionofadietistoprovideatleast300calories,36unitsofvitaminA,and90unitsofvitamin
Cdaily.AcupofdietarydrinkXprovides60calories,12unitsofvitaminA,and10unitsofvitaminC.A
cupofdietarydrinkYprovides60calories,6unitsofvitaminA,and30unitsofvitaminC.Setupasystem
oflinearinequalitiesthatdescribestheminimumdailyrequirementsforcaloriesandvitamins.Let
x=numberofcupsofdietarydrinkX,andy=numberofcupsofdietarydrinkY.Writealltheconstraints
asasystemoflinearinequalities.
A)
60x+60y≥300
12x+6y≥36
10x+30y≥90
x≥0
y≥0
B)
60x+60y>300
12x+6y>36
10x+30y>90
x>0
y>0
C)
60x+60y≥300
12x+6y>36
10x+30y≥90
D)
60x+60y≤300
12x+6y≤36
10x+30y≤90
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2 SolveaLinearProgrammingProblem
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Findthemaximumorminimumvalueofthegivenobjectivefunctionofalinearprogrammingproblem.Thefigure
illustratesthegraphofthefeasiblepoints.
1) z=2x+6y.Findmaximumandminimum.
x
y
(0, 8) (6, 8)
(6, 1)
(
2
,
0
)
(0, 2)
x
y
(0, 8) (6, 8)
(6, 1)
(
2
,
0
)
(0, 2)
A) maximumvalue:60;minimumvalue:4 B) maximumvalue:60;minimumvalue:12
C) maximumvalue:18;minimumvalue:4 D) maximumvalue:18;minimumvalue:12
Findthemaximumorminimumvalueofthegivenobjectivefunctionofalinearprogrammingproblem.Thefigure
illustratesthegraphoffeasiblepoints.
2) z=x+7y.Findmaximum.
A) maximum:37 B) maximum:24 C) maximum:18 D) maximum:30
3) z=–x–9y.Findmaximum.
A) maximum:–22 B) maximum:–30 C) maximum:–47 D) maximum:–38
4) z=6x+7y.Findminimum.
A) minimum:38 B) minimum:39 C) minimum:47 D) nominimum
5) z=x+7y+9.Findminimum.
A) minimum:27 B) minimum:46 C) minimum:34 D) nominimum
6) z=–6x–y.Findmaximum.
A) maximum:–17 B) maximum:–21 C) maximum:–26 D) nomaximum
Solvethelinearprogrammingproblem.
7) Maximizeandminimizez=8x+6ysubjectto:
x≥0, y≥0, 2x+3y≥6, x≤10, y≤5.
A) maximum:110;minimum:12 B) maximum:80;minimum:18
C) maximum:30;minimum:18 D) maximum:110;minimum:80
Page119
8) Minimizez=13x+8y+17subjectto:
x≥0, y≥0, x+y≥1.
A) minimum:25 B) minimum:30 C) minimum:38 D) minimum:17
9) Maximizeandminimizez=5x–11ysubjectto:
x≥0, y≥0, 4x+5y≤30, 4x+3y≤20, x≤5, y≤8.
A) maximum:25;minimum:–66 B) maximum:25;minimum:0
C) maximum:–48.75;minimum:–66 D) maximum:–66;minimum:0
Anobjectivefunctionandasystemoflinearinequalitiesrepresentingconstraintsaregiven.Graphthesystemof
inequalitiesrepresentingtheconstraints.Findthevalueoftheobjectivefunctionateachcornerofthegraphed
region.Usethesevaluestodeterminethemaximumvalueoftheobjectivefunctionandthevaluesofxandyfor
whichthemaximumoccurs.
10) ObjectiveFunction z=20x+15y
Constraints 0≤x≤10
0≤y≤5
3x+2y≥6
A) maximum:275;at(10,5) B) maximum:200;at(10,0)
C) maximum:75;at(0,5) D) maximum:45;at(0,3)
11) ObjectiveFunction z=6x+7y
Constraints x≥0
y≥0
2x+3y≤12
2x+y≤8
A) maximum32;at(3,2) B) maximum32;at(2,3)
C) maximum52;at(4,4) D) maximum24;at(4,0)
12) ObjectiveFunction z=3x+5y
Constraints x≥0
y≥0
2x+y≤15
x–3y≥–3
A) maximum33;at(6,3) B) maximum75;at(0,15)
C) maximum22.5;at(7.5,0) D) maximum38;at(6,4)
13) ObjectiveFunction z=7x–18y
Constraints 0≤x≤5
0≤y≤8
4x+5y≤30
4x+3y≤20
A) maximum:35;at(5,0) B) maximum:0;at(0,0)
C) maximum:–81.25;at(1.25,5) D) maximum:–108;at(0,6)
14) ObjectiveFunction z=5x+6y
Constraints x≥0
0≤y≤5
2x+3y≥12
2x+3y≤20
A) maximum:50;at(10,0) B) maximum:40;at(2,5)
C) maximum:30;at(6,0) D) maximum:–20;at(4,0)
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15) ObjectiveFunction z=6x–4y
Constraints x≥0
0≤y≤2
x–y≤3
x+2y≤6
A) maximum:20;at(4
,
1) B) maximum:18;at(3
,
0)
C) maximum:4;at(2,2) D) maximum:–8;at(0,2)
16) ObjectiveFunction z=7x+6y
Constraints x≥0
y≥0
3x+y≤21
x+y≤10
x+2y≥12
A) maximum65.5;at(5.5,4.5) B) maximum60;at(6,3)
C) maximum68;at(8,2) D) maximum66;at(6,4)
Solvethelinearprogrammingproblem.
17) Twokindsofcratedcargo,AandB,aretobeshippedbytruck.Theweightandvolumeofeachtypeare
giveninthefollowingtable:
AB
Volume 50cubicfeet 10cubicfeet
Weight 200pounds 360pounds
Theshippingcompanycharges$75percrateforcargoAand$100percrateforcargoB.Thetruckhasa
maximumloadlimitof7,200poundsand1,000cubicfeet.Howmanyofeachtypeofcargoshouldbe
shippedtomaximizeprofitfortheshippingcompany?
A) 18cratesofcargoAand10cratesofcargoBB)2
0cratesofcargoAand0cratesofcargoB
C) 0cratesofcargoAand20cratesofcargoBD)10cratesofcargoAand18cratesofcargoB
18) Avineyardproducestwospecialwines,awhiteandared.Abottleofthewhitewinerequires14pounds
ofgrapesand1hourofprocessingtime.Abottleofredwinerequires25poundsofgrapesand2hoursof
processingtime.Thevineyardhasonhand2,198poundsofgrapesandcanallot160hoursofprocessing
timetotheproductionofthesewines.Abottleofthewhitewinesellsfor$11.00,whileabottleofthered
winesellsfor$20.00.Howmanybottlesofeachtypeshouldthevineyardproduceinordertomaximize
grosssales?
A) 132bottlesofwhiteand14bottlesofred B) 14bottlesofwhiteand132bottlesofred
C) 76bottlesofwhiteand42bottlesofred D) 42bottlesofwhiteand59bottlesofred
19) Mrs.Whitewantstocrochetbeachhatsandbabyafghansforachurchfund–raisingbazaar.Sheneeds8
hourstomakeahatand3hourstomakeanafghanandshehas59hoursavailable.Shewantstomakeno
morethan13itemsandnomorethan12afghans.Thebazaarwillsellthehatsfor$14eachandtheafghans
for$7each.Howmanyofeachshouldshemaketomaximizetheincomeforthebazaar?Whatisthe
maximumincome?
A) 4hats,9afghans,$119 B) 9 hats,4 afghans,$154
C) 12hats,1afghans,$175 D) 6 hats,7 afghans,$133
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20) Acandycompanyhas120poundsofcashewsand150 poundsofpeanutswhichtheycombineintotwo
differentmixes.Thedeluxemixhashalfcashewsandhalfpeanutsandsellsfor$6perpound.The
economymixhasonethirdcashewsandtwothirdspeanutsandsellsfor$5.30perpound.Howmany
poundsofeachmixshouldbepreparedformaximumrevenue?
A) 180deluxe,90economy B) 270 deluxe,60 economy
C) 90deluxe,30economy D) 120 deluxe,0economy
21) Adoctorhastoldasickpatienttotakevitaminpills.Thepatientneedsatleast6unitsofvitaminAanda
t
least6unitsofvitaminB.Theredvitaminpillscost10¢eachandcontain1unitofAand2unitsofB.The
bluevitaminpillscost25¢eachandcontain2unitsofAand1unitofB.Toavoidindigestion,thepatient
shouldtakenomorethan4redpillsandnomorethan7bluepills.Howmanypillsshouldthepatienttake
eachdaytominimizecosts?
A) 4redand1blue B) 2redand2blue C) 0redand6blue D) 4redand7blue
22) Adoctorhastoldapatienttotakevitaminpills.Thepatientneedsatleast12unitsofvitaminAanda
t
least8unitsofvitaminD.Theredvitaminpillscost20¢eachandcontain3unitsofAand1unitofD.The
bluevitaminpillscost35¢eachandcontain2unitsofAand2unitsofD.Toavoidindigestion,thepatient
shouldtakenomorethan6redpillsandnomorethan9bluepills.Howmanypillsshouldthepatienttake
eachdaytominimizecosts?
A) 2redand3blue B) 6redand1blue C) 0redand9blue D) 6redand9blue
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
23) Yourcomputersupplystoresellstwotypesoflaserprinters.Thefirsttype,A,hasacostof$86andyou
makea$45profitoneachone.Thesecondtype,B,hasacostof$130andyoumakea$35profitoneach
one.Youexpecttosellatleast100laserprintersthismonthandyouneedtomakeatleast$3850profiton
them.Howmanyofwhattypeofprintershouldyouorderifyouwanttominimizeyourcost?
24) TheJillsonʹshaveupto$75,000toinvest.Theydecidethattheywanttohaveatleast$25,000investedin
stablebondsyielding6%andthatnomorethan$45,000shouldbeinvestedinmorevolatilebonds
yielding12%.Howmuchshouldtheyinvestineachtypeofbondtomaximizeincomeiftheamountinthe
morevolatilebondshouldnotexceedtheamountinthemorestablebond?Whatisthemaximumincome?
25) TheFiedlerfamilyhasupto$130,000toinvest.Theydecidethattheywanttohaveatleast$40,000
investedinstablebondsyielding5.5%andthatnomorethan$60,000shouldbeinvestedinmorevolatile
bondsyielding11%.Howmuchshouldtheyinvestineachtypeofbondtomaximizeincomeiftheamount
inthestablebondshouldnotexceedtheamountinthemorevolatilebond?Whatisthemaximum
income?
26) EricʹsCarpentrymanufacturestwotypesofbookshelvesthatare4feettalland3feetwide,abasicmodel
andadeluxemodel.Eachbasicbookshelfrequires1.5hoursforassemblyand1hourforfinishing;each
deluxemodelrequires2.5hoursforassemblyand1hourforfinishing.Twoassemblersandonefinisher
areemployedbythecompany,andeachworks40hoursperweek.Ericcansellmorebasicmodelsthan
deluxemodels,sohewantsthenumberofbasicmodelsproducedtobe50%morethanthenumberof
deluxemodelsproduced.Ifhemakes$50profitonthebasicmodelsand$65profitonthedeluxemodels,
howmanyshouldhemaketomaximizetheprofit?Whatisthemaximumprofit?
27)
J
oelyʹsTeaShop,astorethatspecializesinteablends,hasavailable45poundsofAgradeteaand70
poundsofBgradetea.Thesewillbeblendedinto1poundpackagesasfollows:Abreakfastblendthat
containsonethirdofapoundofAgradeteaandtwothirdsofapoundofBgradeteaandanafternoon
teathatcontainsonehalfpoundofAgradeteaandonehalfpoundofBgradetea.IfJoelymakesaprofit
of$1.50oneachpoundofthebreakfastblendand$2.00profitoneachpoundoftheafternoonblend,how
manypoundsofeachblendshouldshemaketomaximizeprofits?Whatisthemaximumprofit?
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28) Anartistiscreatingamosaicthatcannotbelargerthanthespaceallottedwhichis4feettalland6fee
t
wide.Themosaicmustbeatleast3feettalland5feetwide.Thetilesinthemosaichavewordswrittenon
themandtheartistwantsthewordstoallbehorizontalinthefinalmosaic.Thewordtilescomeintwo
sizes:Thesmallertilesare4inchestalland4incheswide,whilethelargetilesare6inchestalland12
incheswide.Ifthesmalltilescost$3.50eachandthelargertilescost$4.50each,howmanyofeachshould
beusedtominimizethecost?Whatistheminimumcost?
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
29) TheAcmeClassRingCompanydesignsandsellstwotypesofrings:theVIPandtheSST.Theycan
produceupto24ringseachdayusingupto60totalman–hoursoflabor.Ittakes3man–hourstomake
oneVIPringand2man–hourstomakeoneSSTring.Howmanyofeachtypeofringshouldbemade
dailytomaximizethecompanyʹsprofit,iftheprofitonaVIPringis$40andonanSSTringis$35?
A) 12VIPand12SST B) 14VIPand10SST C) 16VIPand8SST D) 18VIPand6SST
30) Anairlinewithtwotypesofairplanes,P1andP2
,
hascontractedwithatourgrouptoprovide
transportationforaminimumof400firstclass,750touristclass,and1500economyclasspassengers.Fora
certaintrip,airplaneP1costs$10,000tooperateandcanaccommodate20firstclass,50touristclass,and
110economyclasspassengers.AirplaneP2costs$8500tooperateandcanaccommodate18firstclass,30
touristclass,and44economyclasspassengers.Howmanyofeachtypeofairplaneshouldbeusedin
ordertominimizetheoperatingcost?
A) 9P1planesand13P2planes B) 5P1planesand17P2planes
C) 11P1planesand7P2planes D) 7P1planesand11P2planes
31) Asummercampwantstohirecounselorsandaidestofillitsstaffingneedsatminimumcost.Theaverage
monthlysalaryofacounseloris$2400andtheaveragemonthlysalaryofanaideis$1100.Thecampcan
accommodateupto45staffmembersandneedsatleast30torunproperly.Theymusthaveatleast10
aides,andmayhaveupto3aidesforevery2counselors.Howmanycounselorsandhowmanyaides
shouldthecamphiretominimizecost?
A) 12counselorsand18aides B) 27counselorsand18aides
C) 35counselorsand10aides D) 18counselorsand12aides
Ch.12 SystemsofEquationsandInequalities
AnswerKey
12.1 SystemsofLinearEquations:SubstitutionandEliminatio
n
1 SolveSystemsofEquationsbySubstitution
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