document.write( "Question 606222: john drove home at 40 mph. average speed on return is 24mph. return trip took 1/2 hour longer because of traffic. how for did she travel to appointment \n" ); document.write( "

Algebra.Com's Answer #381960 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+d+=+r%2At+\"$
\n" ); document.write( "On 1st trip,
\n" ); document.write( " $\"+r%5B1%5D+=+40+\"$ mi/hr
\n" ); document.write( "(1) $\"+d+=+40t%5B1%5D+\"$
\n" ); document.write( "-----------
\n" ); document.write( "On 2nd trip,
\n" ); document.write( " $\"+r%5B2%5D+=+24+\"$ mi/hr
\n" ); document.write( " $\"+t%5B2%5D+=+t%5B1%5D+%2B+.5+\"$
\n" ); document.write( "(2) $\"+d+=+24%2A%28+t%5B1%5D+%2B+.5+%29+\"$
\n" ); document.write( "-----------
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+40t%5B1%5D+=+24t%5B1%5D+%2B+12+\"$
\n" ); document.write( " $\"+16t%5B1%5D+=+12+\"$
\n" ); document.write( " $\"+t%5B1%5D+=+.75+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+d+=+40t%5B1%5D+\"$
\n" ); document.write( "(1) $\"+d+=+40%2A.75+\"$
\n" ); document.write( "(1) $\"+d+=+30+\"$
\n" ); document.write( "The appointment is 30 mi away
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+d+=+24%2A%28+t%5B1%5D+%2B+.5+%29+\"$
\n" ); document.write( "(2) $\"+d+=+24%2A%28+.75+%2B+.5+%29+\"$
\n" ); document.write( "(2) $\"+d+=+24%2A1.25+%7D%7D%0D%0A%282%29+%7B%7B%7B+d+=+30+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );