Three trains one eastbound, one westbound, and one northbound leave a city at the same time.
The speed of the northbound train is 30 miles per hour greater than the speed of the eastbound
train. After 2 hours, the distance between the westbound train and the eastbound train is 160 miles.
Twice the speed of the westbound train is 40 miles per hour more than the speed of the northbound
train. Find the speeds of the three trains.
eastbound, 40 mph; westbound, 50 mph; northbound, 70 mph
eastbound, 20 mph; westbound, 60 mph; northbound, 60 mph
eastbound, 60 mph; westbound, 50 mph; northbound, 30 mph
eastbound, 30 mph; westbound, 50 mph; northbound, 60 mph
Determine whether the given ordered pair is a solution of the system.
(–4, –2)
4x + y = – 14
2x + 4y =0
The following is known about three numbers: If the second number is subtracted from the sum of
the first number and 4 times the third number, the result is 13. The third number plus 2 times the
first number is 4. The first number plus 5 times the second number plus the third number is 19.
Find the three numbers.
[Hint: let x represent the first number, y the second number, and z the third number. Use the given
conditions to write and solve a system of equations.]
Determine if the given ordered triple is a solution of the system.
(2, 5, –3)
x + y + z =4
x – y + 3z = – 2
2x + y + z =1