SOLUTION: Mikayla went on a 60 mile trip to a soccer game. On the way back, due to road construction she had to drive 8 miles per hour slower. This made the trip take 10 hours longer. How fa

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Mikayla went on a 60 mile trip to a soccer game. On the way back, due to road construction she had to drive 8 miles per hour slower. This made the trip take 10 hours longer. How fa      Log On

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Question 819213: Mikayla went on a 60 mile trip to a soccer game. On the way back, due to road construction she had to drive 8 miles per hour slower. This made the trip take 10 hours longer. How fast did she drive to the soccer game?
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
let speed to go be x
time = 60/x
time to return
speed = (x-8)
d=60
time = 60/(x-8)
return time - to go time = 10 hours
60/(x-8)-60/x=10
LCD = x(x-8)
(60x-60(x-8))/x(x-8)=10
60x-60x+480=10x(x-8)
480=10x^2-80x
10x^2-80x-480=0
/10
x^2-8x-48=0
x2-12x+4x-48=0
(x-12)(x+4)=0
x=12 OR -4
speed cannot be negative
speed going is 12 mph