document.write( "Question 1016791: greg drove at a constant speed in a rainstorm for 252 miles. he took a break, and the rain stopped. he then drove 144 miles at a speed that was six miles per hour faster than his previous speed. if he drove for 9 hours, find the cars speed for each part of the trip. \n" ); document.write( "
Algebra.Com's Answer #633202 by josmiceli(19441)\"\" \"About 
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Let \"+s+\" = his speed in mi/hr for
\n" ); document.write( "driving during rainstorm
\n" ); document.write( "Let \"+t+\" = his time in hrs for
\n" ); document.write( "driving during rainstorm
\n" ); document.write( "-----------------------------
\n" ); document.write( "Equation for driving during rainstorm:
\n" ); document.write( "(1) \"+252+=+s%2At+\"
\n" ); document.write( "Equation for driving after rainstorm:
\n" ); document.write( "(2) \"+144+=+%28+s%2B6+%29%2A%28+9+-+t+%29+\"
\n" ); document.write( "-----------------------------
\n" ); document.write( "(1) \"+t+=+252%2Fs+\"
\n" ); document.write( "and
\n" ); document.write( "(2) \"+144+=+9s+%2B+54+-+s%2At+-+6t+\"
\n" ); document.write( "(2) \"+144+=+9s+%2B+54+-+t%2A%28+s+%2B+6+%29+\"
\n" ); document.write( "(2) \"+144+=+9s+%2B+54+-%28+252%2Fs+%29%2A%28+s+%2B+6+%29+\"
\n" ); document.write( "(2) \"+144+=+9s+%2B+54+-+252+-+1512%2Fs+\"
\n" ); document.write( "(2) \"+144+%2B+252+-+54+=+9s+-+1512%2Fs+\"
\n" ); document.write( "(2) \"+342+=+9s+-+1512%2Fs+\"
\n" ); document.write( "(2) \"+342s+=+9s%5E2+-+1512+\"
\n" ); document.write( "(2) \"+9s%5E2+-+342s+-+1512+=+0+\"
\n" ); document.write( "(2) \"+s%5E2+-+38s+-+168+=+0+\"
\n" ); document.write( "Use quadratic equation
\n" ); document.write( "\"+s+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "\"+a+=+1+\"
\n" ); document.write( "\"+b+=+-38+\"
\n" ); document.write( "\"+c+=+-168+\"
\n" ); document.write( "\"+s+=+%28-%28-38%29+%2B-+sqrt%28+%28-38%29%5E2-4%2A1%2A%28-168%29+%29%29%2F%282%2A1%29+\"
\n" ); document.write( "\"+s+=+%28+38+%2B-+sqrt%28+1444+%2B+672+%29%29%2F2+\"
\n" ); document.write( "\"+s+=+%28+38+%2B-+sqrt%28+2116+%29%29%2F2+\"
\n" ); document.write( "\"+s+=+%28+38+%2B+46%29%2F2+\"
\n" ); document.write( "\"+s+=+84%2F2+\"
\n" ); document.write( "\"+s+=+42+\"
\n" ); document.write( "and
\n" ); document.write( "\"+s+%2B+6+=+48+\"
\n" ); document.write( "---------------
\n" ); document.write( "His speed during rainstorm was 42 mi/hr
\n" ); document.write( "His speed after rainstorm was 48 mi/hr
\n" ); document.write( "----------
\n" ); document.write( "check:
\n" ); document.write( "(1) \"+252+=+s%2At+\"
\n" ); document.write( "(1) \"+252+=+42t+\"
\n" ); document.write( "(1) \"+t+=+6+\" hrs
\n" ); document.write( "-----------------
\n" ); document.write( "(2) \"+144+=+%28+s%2B6+%29%2A%28+9+-+t+%29+\"
\n" ); document.write( "(2) \"+144+=+48%2A%28+9+-+t+%29+\"
\n" ); document.write( "(2) \"+144+=+432+-+48t+\"
\n" ); document.write( "(2) \"+48t+=+288+\"
\n" ); document.write( "(2) \"+t+=+6+\" hrs
\n" ); document.write( "OK
\n" ); document.write( "
\n" );