SOLUTION: For his morning workout a boxer bicycles for 8 miles and then jogs back to camp along the same route. If he bicycles 6 mph faster than he jogs, and the entire workout lasts 2 hours

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Question 438086: For his morning workout a boxer bicycles for 8 miles and then jogs back to camp along the same route. If he bicycles 6 mph faster than he jogs, and the entire workout lasts 2 hours, how fast does he jog?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
For his morning workout a boxer bicycles for 8 miles and then jogs back to camp along the same route.
If he bicycles 6 mph faster than he jogs, and the entire workout lasts 2 hours, how fast does he jog?
:
Let x = his jogging speed
then
(x+6) = his biking speed
:
Write a time equation Time = dist/speed
:
Jog time + bike time = 2 hrs
8%2Fx + 8%2F%28%28x%2B6%29%29 = 2
:
multiply by x(x+6), results
8(x+6) + 8x = 2x(x+6)
8x + 48 + 8x = 2x^2 + 12x
16x + 48 = 2x^2 + 12x
:
A quadratic equation
2x^2 + 12x - 16x - 48 = 0
2x^2 - 4x - 48 = 0
:
simplify, divide by 2
x^2 - 2x - 24 = 0
:
Factors to
(x-6)(x+4) = 0
:
x = 6 mph is the jogging speed
:
:
Check this by finding the times
8/6 = 1.33 hrs jogging
8/12= .67 hrs biking
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total 2 hrs