SOLUTION: Please help!
A car travels 304 mi. A second car, traveling 9 mph faster than the first car, makes the same trip in 1 h less time. Find the speed of each car.
First Car?
Second
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Quadratic Equations and Parabolas
-> SOLUTION: Please help!
A car travels 304 mi. A second car, traveling 9 mph faster than the first car, makes the same trip in 1 h less time. Find the speed of each car.
First Car?
Second
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Question 1113418: Please help!
A car travels 304 mi. A second car, traveling 9 mph faster than the first car, makes the same trip in 1 h less time. Find the speed of each car.
First Car?
Second Car? Answer by ikleyn(52794) (Show Source):
Let r be the speed of the slower car, in mph
Then the speed of the faster car is (r+9) mph.
The "time equation" is
- = 1 ("second car, traveling 9 mph faster than the first car, makes the same trip in 1 h less time")
304*(r+9) - 304r = r*(r+9)
2736 = r^2 + 9r
r^2 + 9r - 2736 = 0
(r-48)*(r+57) = 0
The only positive root is r= 48 mph.
It is the speed of the slower car.
Answer. The speed of the slower car is 48 mph; of the faster car 48+9 = 57 mph.