SOLUTION: After walking a distance of 6 miles at a certain rate, a man decided to increase his rate per hour by 1 mile and walked 5 miles farther. Had he walked the entire distance of 11 mil

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: After walking a distance of 6 miles at a certain rate, a man decided to increase his rate per hour by 1 mile and walked 5 miles farther. Had he walked the entire distance of 11 mil      Log On


   

Question 909780: After walking a distance of 6 miles at a certain rate, a man decided to increase his rate per hour by 1 mile and walked 5 miles farther. Had he walked the entire distance of 11 miles at his former rate, his time would have been 15 minutes longer. Find his former rate.
Answer by lwsshak3(11628) About Me  (Show Source):
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After walking a distance of 6 miles at a certain rate, a man decided to increase his rate per hour by 1 mile and walked 5 miles farther. Had he walked the entire distance of 11 miles at his former rate, his time would have been 15 minutes longer. Find his former rate.
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let x=former rate
x+1=increased rate
15 min=1/4 hr
travel time=distance/rate
..
11%2Fx-%286%2Fx%2B5%2F%28x%2B1%29%29=1%2F4
11%2Fx-6%2Fx-5%2F%28x%2B1%29%29=1%2F4
%285%2Fx%29-%285%2F%28x%2B1%29%29=1%2F4
lcd:x(x+1)
5x+5-5x=(x^2+x)/4
20x+20-20x=x^2+x
x^2+x-20=0
(x+5)(x-4)=0
x=4
x+1=5
former rate=4 mph