document.write( "Question 891313: Amy drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 8 hours. When Amy drove home, there was no traffic and the trip only took 5 hours. If her average rate was 21 miles per hour faster on the trip home, how far away does Amy live from the mountains?
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Algebra.Com's Answer #539664 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "I put in some numbers.\r\n" );
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\n" ); document.write( "Amy drove to the mountains last weekend. There was heavy traffic on the way
\n" ); document.write( "there, and the trip took 8 hours. When Amy drove home, there was no traffic and
\n" ); document.write( "the trip only took 5 hours. If her average rate was 21 miles per hour faster on
\n" ); document.write( "the trip home, how far away does Amy live from the mountains?
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document.write( "Make this chart:\r\n" );
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document.write( "             | Distance |  rate | time\r\n" );
document.write( "--------------------------------------\r\n" );
document.write( "To mountains |          |       |  \r\n" );
document.write( "To home      |          |       |  \r\n" );
document.write( "

\n" ); document.write( "how far away does Amy live from the mountains?

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document.write( "Suppose Amy lives x miles from the mountains.\r\n" );
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document.write( "Fill in x as both distances and the times\r\n" );
document.write( "going and coming 8 hours and 5 hours.  \r\n" );
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document.write( "             | Distance |  rate | time\r\n" );
document.write( "To mountains |    x     |       |  8\r\n" );
document.write( "Coming home  |    x     |       |  5\r\n" );
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document.write( "to fill in the two rate boxes:\r\n" );
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document.write( "             | Distance |  rate | time\r\n" );
document.write( "To mountains |    x     |  x/8  |  8\r\n" );
document.write( "Coming home  |    x     |  x/5  |  5\r\n" );
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document.write( "The equation comes from this sentence:\r\n" );
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document.write( "

>>...her average rate was 21 miles per hour faster on the trip home...<<

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document.write( "       \r\n" );
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document.write( "  \r\n" );
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document.write( "Multiply through by LCD=40.\r\n" );
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document.write( "  \r\n" );
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document.write( "Subtract 5x from both sides:\r\n" );
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document.write( "  \r\n" );
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document.write( "Divide both sides by 3\r\n" );
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document.write( "  \r\n" );
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document.write( "So Amy lives 280 miles from the mountains.\r\n" );
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document.write( "Edwin

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