A question about (Solving a distance, rate, time problem using a system of linear equations)

Question

Two buses leave a station at the same time and travel in opposite directions. One bus travels 13

 mih

 faster than the other. If the two buses are 945

 miles apart after 7

 hours, what is the rate of each bus?

Answer 1

7x + 7(x+13) = 945

mph x time = distance

7x + 7x = 945 - 91

14x = 854

x = 854/14 = 61 mph for slower bus

x+13 = 74 mph for faster bus

in 7 hours they're 7 times (61+74) = 7(135) = 945 miles apart