document.write( "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 \n" ); document.write( "

Algebra.Com's Answer #625380 by stanbon(75887) $\"\"$ $\"About$

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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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\n" ); document.write( "Slower rate DATA:
\n" ); document.write( "distance = 280 miles ; rate = x mph ; time = d/r = 280/x hrs
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\n" ); document.write( "Faster rate DATA:
\n" ); document.write( "distance = 280 miles ; rate = x+5 mph ; time = 280/(x+5)
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\n" ); document.write( "Equation:
\n" ); document.write( "time - time = 1 hr
\n" ); document.write( "280/x - 280/(x+5) = 1 hr
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\n" ); document.write( "280x + 280*5 - 280x = x(x+5)
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\n" ); document.write( "1400 = x^2+5x
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\n" ); document.write( "x^2 + 5x - 1400 = 0
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\n" ); document.write( "x = 35 mph (speed of the truck)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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