document.write( "Question 1094907: Darren drives to school in rush hour traffic and averages 21 mph. He returns home in mid-afternoon when there is less traffic and averages 42 mph. What is the distance between his home and school if the total traveling time is 1hr30min?
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Algebra.Com's Answer #709477 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+t+\"$ = travel time in hrs going to school
\n" ); document.write( " $\"+1.5+-+t+\"$ = travel time in hrs going home
\n" ); document.write( "Let $\"+d+\"$ = the one-way distance in miles to school
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\n" ); document.write( "Equation for going to school:
\n" ); document.write( "(1) $\"+d+=+21t+\"$
\n" ); document.write( "Equation for going home:
\n" ); document.write( "(2) $\"+d+=+42%2A%28+1.5+-+t+%29+\"$
\n" ); document.write( "----------------------------
\n" ); document.write( "Set (1) = (2)
\n" ); document.write( " $\"+21t+=+42%2A%28+1.5+-+t+%29+\"$
\n" ); document.write( " $\"+21t+=+63+-+42t+\"$
\n" ); document.write( " $\"+63t+=+63+\"$
\n" ); document.write( " $\"+t+=+1+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "(1) $\"+d+=+21t+\"$
\n" ); document.write( "(1) $\"+d+=+21%2A1+\"$
\n" ); document.write( "(1) $\"+d+=+21+\"$
\n" ); document.write( "The distance between home and school is 21 miles
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\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+d+=+42%2A%28+1.5+-+t+%29+\"$
\n" ); document.write( "(2) $\"+d+=+42%2A%28+1.5+-+1+%29+\"$
\n" ); document.write( "(2) $\"+d+=+42%2A.5+\"$
\n" ); document.write( "(2) $\"+d+=+21+\"$
\n" ); document.write( "OK \n" ); document.write( "

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