Algebra
posted by Megan Brown on .
Two trans leave Chicago going opposite directions, one going north and the other going south. The northbound train is traveling 12 mph slower than the southbound train. After 4 hours the trains are 528 miles apart. Find the speed of each train. I would appreciated so much if anyone could give me directions on the question.

RT = D (Rate x Time = Distance)
R = rate of southbound train
4 = time of southbound
4R = distance of southbound train
R  12 = rate of northbound train
4 = time of northbound
4(R  12) = distance of northbound train
Since the sum of distances = 528
4R + 4(R  12) = 528
Solve for R, rate of southbound train
R  12 = rate of northbound train 
Northbound train is traveling at 60 mph, the other 72.