SOLUTION: Two trains are going in opposite directions leave at the same time. Train b travels 10 mph faster than A. In 3 hours the trains are 360 miles apart. Find the speeds for each

Let u be the speed of the train A (slower train), in miles-per-hour (mph).
Then the faster train (train B) has the speed u+10 mph.


Your equation is 

3*u + 3*(u+10) = 360.

Simplify and solve:

3u + 3u + 30 = 360,

6u = 360-30 = 330,

u =  = 55 mph.

Answer. Train A has the speed 55 mph, train B 55 + 10 = 65 mph.