document.write( "Question 760016: Julie took 2 hours longer to drive 600 miles on the first day of a trip than she took to drive 500
\n" ); document.write( "miles on the second day. If her speed was the same both days, what was the driving time for
\n" ); document.write( "each day? \n" ); document.write( "

Algebra.Com's Answer #462365 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+t+\"$ = her time in hrs for the 2nd day
\n" ); document.write( " $\"+t+%2B+2+\"$ = her time in hrs for the 1st day
\n" ); document.write( " $\"+r+\"$ = her speed on both days
\n" ); document.write( "----------------
\n" ); document.write( "1st day:
\n" ); document.write( "(1) $\"+600+=+r%2A%28+t+%2B+2+%29+\"$
\n" ); document.write( "2nd day:
\n" ); document.write( "(2) $\"+500+=+r%2At+\"$
\n" ); document.write( "----------------
\n" ); document.write( "This is 2 equations with 2 unknowns, so it's solvable
\n" ); document.write( "(2) $\"+r+=+500%2Ft+\"$
\n" ); document.write( "and, by substitution:
\n" ); document.write( "(1) $\"+600+=+%28+500%2Ft+%29%2A%28+t+%2B+2+%29+\"$
\n" ); document.write( "(1) $\"+600+=+500+%2B+1000%2Ft+\"$
\n" ); document.write( "(1) $\"+100+=+1000%2Ft+\"$
\n" ); document.write( "(1) $\"+100t+=+1000+\"$
\n" ); document.write( "(1) $\"+t+=+10+\"$
\n" ); document.write( " $\"+t+%2B+2+=+12+\"$
\n" ); document.write( "Her time for the 1st day was 12 hrs
\n" ); document.write( "Her time for the 2nd day was 10 hrs
\n" ); document.write( "check:
\n" ); document.write( "(1) $\"+600+=+r%2A%28+t+%2B+2+%29+\"$
\n" ); document.write( "(1) $\"+600+=+r%2A%28+10+%2B+2+%29+\"$
\n" ); document.write( "(1) $\"+12r+=+600+\"$
\n" ); document.write( "(1) $\"+r+=+50+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+500+=+r%2At+\"$
\n" ); document.write( "(2) $\"+500+=+r%2A10+\"$
\n" ); document.write( "(2) $\"+r+=+50+\"$
\n" ); document.write( "OK\r
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