Answer:
Explanation:
One rider's rate is x....the other is x+4
Once they pass each other, they travel for 1.5 hrs...and the combined distance they travel = 39 km
So....Rate x Time = Distance....and we have
x(1.5) + (x+4)(1.5) = 39 simplify
1.5x + 1.5x + 6 = 39
3x + 6 = 39 subtract 6 from both sides
3x = 33 divide by 3 on both sides
x = 11 km/hr this si the slower rider's rate
x + 4 = 11 + 4 = 15 km/hr and this is the faster rider's rate