Two trains leave the depot at the same time one traveling ea

Two trains leave the depot at the same time, one traveling east and the other west. The speed of one train is 9mph slower than the other. If after 4 hours the distance between the trains is 196 miles find the speed of each train.

Solution

x=speed of one train
x-9=speed of the other train
mph(hr)=total distance

4(x)+4(x-9)=196---------------------------------because the sum of 4 hours times both speeds will give you the total distance

Simplify
4x+4x-36=196

Combine like terms
8x-36=196

Add 36 to each side
8x=232

Divide by 8
x=29

[x=speed of one train]
[x-9=speed of the other train]

speed of one train= 29mph
speed of the other train= 20mph