Question 186557This question is from textbook
: A man rode a bicycle for 12 miles and then hiked an additional 8 miles. The total time for the trip was 5 hours. If his rate when he was riding a bicycle was 10 miles per hour faster than his rate walking, what was each rate?
D = R x T
bike 12 mi r+10 5 hr
hike 8 mi r 5 hr
Am i on the right track?
This question is from textbook
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A man rode a bicycle for 12 miles and then hiked an additional 8 miles. The total time for the trip was 5 hours. If his rate when he was riding a bicycle was 10 miles per hour faster than his rate walking, what was each rate?
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Walking DATA:
distance = 8 miles ; rate = x mph ; time = 8/x hrs.
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Biking DATA:
distance = 12 miles : rate = (x+10)mph ; time = 12/(x+10) hrs
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Equation:
8/x + 12/(x+10) = 5
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Multiply thru by x(x+10) you get:
8(x+10) + 12x = 5x(x+10)
8x + 80 + 12x = 5x^2 + 50x
5x^2 + 30x - 80 = 0
x^2 + 6x - 16 = 0
(x+8)(x-2) = 0
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Positive solution:
x = 2 mph (walking rate)
x+10 = 12 mph (bicycling rate)
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Cheers,
Stan H.
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