distance, rate, time problem with linear equation

Question

Two trains leave the station at the same time, one heading east and the other west. The eastbound train travels 18

 miles per hour slower than the westbound train. If the two trains are 510

 miles apart after 3

 hours, what is the rate of the eastbound train?

Answer 1

3( R + R-18) = 510

2r - 18 = 170

2r = 188

r = 94

westbound train speed is 94

eastbound train speed is 76