I have having problem solving this.
One train leaves a station heading due west. Two hours later a second train leaves the same station heading due east. The second train is traveling 15 mi/hr faster than the first. Six hours after the second train leaves, the two trains are 580 miles apart. Find the rate at which east train is traveling.
Try setting up the information explicitly in terms of the "d = rt" equation.
. . . . .first train:
. . . . .rate: r
. . . . .time: 2 + 6 = 8
. . . . .distance: 8r
. . . . .second train:
. . . . .rate: r + 15
. . . . .time: 6
. . . . .distance: 6(r + 15) = 6r + 90
They are headed in opposite directions, so the distance between them is the sum of their two distances:
. . . . .total distance:
. . . . .8r + 6r + 90 = 580
Then:
. . . . .14r = 490
Divide through by 14 to find the rate of the first train. Back-solve to find the rate of the second train.
Have fun!