document.write( "Question 517035: The stopping distance d of a car after the breaks are applied varies directly as the square of the speed r. If a car traveling 40 mph can stop in 90 ft, how many feet will it take the same car to stop when it is traveling 60mph? \n" ); document.write( "
Algebra.Com's Answer #344614 by stanbon(75887)\"\" \"About 
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The stopping distance d of a car after the breaks are applied varies directly as the square of the speed r.
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\n" ); document.write( "d = k*r^2
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\n" ); document.write( "If a car traveling 40 mph can stop in 90 ft, how many feet will it take the same car to stop when it is traveling 60mph?
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\n" ); document.write( "Solve for \"k\" using \"a car traveling 40 mph can stop in 90 ft\":
\n" ); document.write( "90 = k*40^2
\n" ); document.write( "k = 90/40^2
\n" ); document.write( "k = 0.0563
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\n" ); document.write( "Equation:
\n" ); document.write( "d = 0.0563*r^2
\n" ); document.write( "how many feet will it take the same car to stop when it is traveling 60mph?
\n" ); document.write( "d = 0.0563*60^2 = 202.5 feet
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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