Distance problem

Question

Rachel started biking to the mall traveling 11 miles per hour after sometime the bike got a flat some Rachel walk the rest of the way traveling 4 miles per hour if the total trip to the mall took 9 hours and it was 57 miles away how long did Rachel travel at 8 speed?

Answer 1

Let B = bike time and W = walk time

B + W = 9

11B + 4W = 57

It is a too up whether elimination or substitution is easier...either way you should be able to handle it.