Find the​ bicyclist's average speed on each part of the trip.

Question

During the first part of a​ trip, a bicyclist travels 51 miles at a certain speed. The return trip is made at a speed that is 6 mph slower. Total time for the round trip is 15 hr. Find the​ bicyclist's average speed on each part of the trip.

The speed on the first part of the trip was _____ mph.

Answer 1

A bicyclist travels 51 miles with speed X mph, round trip he travels with speed X - 6 mph

51 /x + 51 /x-6 = 15 h time he spent on the round trip

5X2 - 64X +102=0

need to find roots of quadratic equation.

That is one speed.

X-6 is the second speed