document.write( "Question 1046151: You drive at an average of 30 miles per hour on the way to work, and at an average of 35 miles per hour on the way home. The total driving time is 30 minutes. How far away is work? Round your answer to the nearest hundredth of a mile. \n" ); document.write( "

Algebra.Com's Answer #661677 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+d+\"$ = the one-way distance to work
\n" ); document.write( "Let $\"+t+\"$ = time in hrs to get to work
\n" ); document.write( " $\"+.5+-+t+\"$ = time in hrs to get home from work
\n" ); document.write( "( note that I converted min to hrs )
\n" ); document.write( "------------------------------------
\n" ); document.write( "Driving to work:
\n" ); document.write( "(1) $\"+d+=+30t+\"$
\n" ); document.write( "Driving home:
\n" ); document.write( "(2) $\"+d+=+35%2A%28+.5+-+t+%29+\"$
\n" ); document.write( "-------------------------
\n" ); document.write( "Plug (1) into (2)
\n" ); document.write( "(2) $\"+30t+=+17.5+-+35t+\"$
\n" ); document.write( "(2) $\"+65t+=+17.5+\"$
\n" ); document.write( "(2) $\"+t+=+.26923+\"$ hrs
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+d+=+30t+\"$
\n" ); document.write( "(1) $\"+d+=+30%2A.26923+\"$
\n" ); document.write( "(1) $\"+d+=+8.077+\"$ mi
\n" ); document.write( "Work is 8.08 mi away
\n" ); document.write( "-----------------------
\n" ); document.write( "check answer:
\n" ); document.write( "(2) $\"+d+=+35%2A%28+.5+-+t+%29+\"$
\n" ); document.write( "(2) $\"+8.077+=+35%2A%28+.5+-+.26923+%29+\"$
\n" ); document.write( "(2) $\"+8.077+=+17.5+-+9.4231+\"$
\n" ); document.write( "(2) $\"+8.077+=+8.0769+\"$
\n" ); document.write( "close enough
\n" ); document.write( " \n" ); document.write( "

\n" );