document.write( "Question 433080: Please help!
\n" ); document.write( "The stopping distance d of a car after the brakes are applied varies directly as the square of the speed r. If a car traveling 60 mph can stop in 200 ft, how many feet will it take the same car to stop when it's traveling 70 mph? \n" ); document.write( "

Algebra.Com's Answer #300186 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
The formula for this takes the form
\n" ); document.write( " $\"+d+=+k%2A%28r%5E2%29+\"$ where $\"k\"$ is the
\n" ); document.write( "so-called \"constant of proportionality\"
\n" ); document.write( "You have to find $\"k\"$ , so
\n" ); document.write( " $\"200+=+k%2A%2860%5E2%29\"$
\n" ); document.write( " $\"200+=+3600k\"$
\n" ); document.write( " $\"+k+=+1%2F18+\"$
\n" ); document.write( "Now, if the car travels $\"70\"$ mi/hr,
\n" ); document.write( " $\"+d+=+%281%2F18%29%2A%2870%5E2%29+\"$
\n" ); document.write( " $\"+d+=+4900+%2F+18+\"$
\n" ); document.write( " $\"+d+=+272.22+\"$ ft \n" ); document.write( "

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