SOLUTION: Michael drove to a friend`s house a rate of 40 mph. he came back by the same route, but at a rate of 45 mph. if the round-trip took 4 hours what is the distance to his friend`s hou
Algebra ->
Angles
-> SOLUTION: Michael drove to a friend`s house a rate of 40 mph. he came back by the same route, but at a rate of 45 mph. if the round-trip took 4 hours what is the distance to his friend`s hou
Log On
Question 323432: Michael drove to a friend`s house a rate of 40 mph. he came back by the same route, but at a rate of 45 mph. if the round-trip took 4 hours what is the distance to his friend`s house? Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! D=RT
D=40T FIRST TRIP
D=45(4-T) RETURN TRIP
THE DISTANCES ARE THE SAME TEREFORE THE EQUATIONS ARE THE SAME.
40T=45(4-T)
40T=180-45T
40t+45T=180
85T=180
T=180/85
T=2.118 HRS. FOR THE FIRST TRIP.
4-2.118=1.88 HRS. FOR THE RETURN TRIP.
PROOF:
40*2.118=45*1.88
84.7~84.7
2*84.7=169.4 MILES IS THE DISTANCE OF THE ROUND TRIP.
(