SOLUTION: a pickup truck is driven 280 miles. if it has traveled 5 miles per hour faster , it would have made the trip an hour shorter. what was the speed of the truck
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Question 1009921: a pickup truck is driven 280 miles. if it has traveled 5 miles per hour faster , it would have made the trip an hour shorter. what was the speed of the truck Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! a pickup truck is driven 280 miles. if it has traveled 5 miles per hour faster , it would have made the trip an hour shorter. what was the speed of the truck
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Slower rate DATA:
distance = 280 miles ; rate = x mph ; time = d/r = 280/x hrs
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Faster rate DATA:
distance = 280 miles ; rate = x+5 mph ; time = 280/(x+5)
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Equation:
time - time = 1 hr
280/x - 280/(x+5) = 1 hr
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280x + 280*5 - 280x = x(x+5)
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1400 = x^2+5x
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x^2 + 5x - 1400 = 0
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x = 35 mph (speed of the truck)
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Cheers,
Stan H.
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