SOLUTION: Amy travels 450 miles at a certain speed. If the car had gone 15mph faster, the trip would have taken one hour less. Find Amy's speed. A. 78 mph B. 75 mph C. 68 mph D. 72 mph

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Amy travels 450 miles at a certain speed. If the car had gone 15mph faster, the trip would have taken one hour less. Find Amy's speed. A. 78 mph B. 75 mph C. 68 mph D. 72 mph      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 22892: Amy travels 450 miles at a certain speed. If the car had gone 15mph faster, the trip would have taken one hour less. Find Amy's speed.
A. 78 mph
B. 75 mph
C. 68 mph
D. 72 mph
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
450(-x+15)=450(-x-1)
-450x+6750=450x-450
-900x=-7200
x=8
15x=450
x=30
30 x 2 because x+x=2x ... 15+x+x=15=2x
60+8
=68
Hence, the speed is 68miles per hour.