document.write( "Question 311811: Working together, Rick and Juanita can complete a job in 6 hours. It would take Rick 9 hours longer than Juanita to do the job alone. How long would it take Juanita alone? \n" ); document.write( "
Algebra.Com's Answer #223010 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Working together, Rick and Juanita can complete a job in 6 hours. \n" ); document.write( " It would take Rick 9 hours longer than Juanita to do the job alone. \n" ); document.write( " How long would it take Juanita alone? \n" ); document.write( ": \n" ); document.write( "Let t = time for J to do it alone \n" ); document.write( "then \n" ); document.write( "(t+9) = time for R to do it alone \n" ); document.write( ": \n" ); document.write( "Let the completed job = 1 \n" ); document.write( ": \n" ); document.write( "A shared work equation: \n" ); document.write( " \n" ); document.write( "Multiply equation by t(t+9), results \n" ); document.write( "6(t+9) + 6t = t(t+9) \n" ); document.write( ": \n" ); document.write( "6t + 54 + 6t = t^2 + 9t \n" ); document.write( "combine on the right \n" ); document.write( "0 = t^2 + 9t - 12t - 54 \n" ); document.write( ": \n" ); document.write( "t^2 - 3t - 54 = 0 \n" ); document.write( "Factor \n" ); document.write( "(t-9)(t+6) = 0 \n" ); document.write( "positive solution \n" ); document.write( "t = 9 hrs J, alone \n" ); document.write( "then \n" ); document.write( "9 + 9 = 18 hrs R alone \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check solution \n" ); document.write( "6/9 + 6/18 = 1\r \n" ); document.write( "\n" ); document.write( ": \n" ); document.write( "Note: Rick only has one arm \n" ); document.write( " \n" ); document.write( " |