document.write( "Question 729664: It takes Bob 4 hours longer to repair a car than it takes Ken. Working together, they can complete the job in 1.5 hours. How long would each of them take working alone. \n" ); document.write( "
Algebra.Com's Answer #446160 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
It takes Bob 4 hours longer to repair a car than it takes Ken. Working together, they can complete the job in 1.5 hours. How long would each of them take working alone.
\n" ); document.write( ".
\n" ); document.write( "Let x = time (hours) it takes ken to do job alone
\n" ); document.write( "then
\n" ); document.write( "x+4 = time it takes bob
\n" ); document.write( ".
\n" ); document.write( "1.5(1/(x+4) + 1/x) = 1
\n" ); document.write( "multiplying both sides by x(x+4):
\n" ); document.write( "1.5(x + x+4) = x(x+4)
\n" ); document.write( "1.5(2x+4) = x^2+4x
\n" ); document.write( "3x+6 = x^2+4x
\n" ); document.write( "6 = x^2+x
\n" ); document.write( "0 = x^2+x-6
\n" ); document.write( "0 = (x+3)(x-2)
\n" ); document.write( "x = {-3, 2}
\n" ); document.write( "throw out negative solution (extraneous) leaving:
\n" ); document.write( "x = 2 hours (Ken)
\n" ); document.write( ".
\n" ); document.write( "Bob:
\n" ); document.write( "x+4 = 2+4 = 6 hours \n" ); document.write( "
\n" );