
ANGELINA C. answered 10/03/19
BSE - Major in Mathematics with 30+ teaching experience.
Let x = the rate of the first train
x + 48 = the rate of the second train
Time of the first train is 4 hours ( the second train left at 4:00 PM , that's 2 hours after the first train left at 2:00PM, then the second train overtook the first train at 6:00 PM, so the fist train has been traveling for 4 hours before the second train overtook it)
Time for the second train is 2 hours, from 4:00 PM to 6:00 PM
Distance = rate x time
Distance traveled by the first train = 4x
Distance traveled by the second train = 2 ( x + 48 )
4x = 2 ( x + 48 ) is the equation
4x = 2x + 96 using the distributive property
2x = 96 subtract 2x from both sides of the equation
x = 48 mph is the rate of the first train
x + 48 = 96 mph is the rate of the second train