7 ModelDatawithLinearFunctionsandMakePredictions
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Solve.
1) Aschoolhasjustpurchasednewcomputerequipmentfor$23,000.00. Thegraphshowsthedepreciationofthe
equipmentover5years.Thepoint(0,23,000)representsthepurchasepriceandthepoint(5,0)representswhen
theequipmentwillbereplaced.Writealinearequationinslope–interceptformthatmodelsthevalueofthe
equipment,y,xyearsafterpurchase.Usethemodeltopredictthevalueoftheequipmentafter3years?
2.5 5
y
25000
22500
20000
17500
15000
12500
10000
7500
5000
2500
2.5 5
y
25000
22500
20000
17500
15000
12500
10000
7500
5000
2500
A) y=–4600x+23,000;
valueafter3yearsis$9200.00;
B) y=23,000x+5;
valueafter3yearsis$9200.00
C) y=4600x–23,000;
valueafter3yearsis$9200.00
D) y= – 23,000x+23,000;
valueafter3yearsis$–46,000.00
2) Theaveragevalueofacertaintypeofautomobilewas$15,600 in1995 anddepreciatedto$4080 in2000.Lety
betheaveragevalueoftheautomobileintheyearx,wherex=0represents1995.Writealinearequationthat
modelsthevalueoftheautomobileintermsoftheyearx.
A) y=–2304x+15,600 B) y= –2304x+4080
C) y=–2304x–7440 D) y=–1
2304 x–4080
3) Aninvestmentisworth$3595in1994.By1998 ithasgrownto$5095.Letybethevalueoftheinvestmentin
theyearx,wherex=0represents1994.Writealinearequationthatmodelsthevalueoftheinvestmentinthe
yearx.
A) y=375x+3595 B) y=1
375 x+3595 C) y= –375x+6595 D) y= –375x+3595
4) Afaucetisusedtoaddwatertoalargebottlethatalreadycontainedsomewater.Afterithasbeenfillingfor5
seconds,thegaugeonthebottleindicatesthatitcontains28ouncesofwater.Afterithasbeenfillingfor12
seconds,thegaugeindicatesthebottlecontains63ouncesofwater.Letybetheamountofwaterinthebottlex
secondsafterthefaucetwasturnedon.Writealinearequationthatmodelstheamountofwaterinthebottlein
termsofx.
A) y=5x+3B)y=1
5x+27 C) y= –5x+53 D) y=5x+51
5) Whenmakingatelephonecallusingacallingcard,acalllasting6 minutescost$1.70.Acalllasting13 minutes
cost$3.10.Letybethecostofmakingacalllastingxminutesusingacallingcard.Writealinearequationthat
modelsthecostofamakingacalllastingxminutes.
A) y=0.2x+0.5 B) y=5x–283
10 C) y= –0.2x+2.9 D) y=0.2x–9.9
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