document.write( "Question 486794: Working together, two men can do a job in 20 days. Working alone, however, it would take one man 9 days longer than it would take the other to complete the job. How long would it take each separately? \n" ); document.write( "
Algebra.Com's Answer #333030 by ankor@dixie-net.com(22740)\"\" \"About 
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Working together, two men can do a job in 20 days.
\n" ); document.write( "Working alone, however, it would take one man 9 days longer than it would take the other to complete the job.
\n" ); document.write( " How long would it take each separately?
\n" ); document.write( ":
\n" ); document.write( "Let t = time required by the 1st man to do the job alone
\n" ); document.write( "then
\n" ); document.write( "(t+9) = time required by the 2nd man alone
\n" ); document.write( ":
\n" ); document.write( "Let the completed job = 1
\n" ); document.write( ":
\n" ); document.write( "A typical shared work equation
\n" ); document.write( ":
\n" ); document.write( "Each man will do a fraction of the job, the two fractions add up to 1
\n" ); document.write( ":
\n" ); document.write( "\"20%2Ft\" + \"20%2F%28t%2B9%29\" = 1
\n" ); document.write( ":
\n" ); document.write( "multiply by t(t+9), results
\n" ); document.write( "20(t+9) + 20t = t(t+9)
\n" ); document.write( "20t + 180 + 20t = t^2 + 9t
\n" ); document.write( ":
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "t^2 + 9t - 40t - 180 = 0
\n" ); document.write( "t^2 - 31t - 180 = 0
\n" ); document.write( ":
\n" ); document.write( "you can solve this using the quadratic equation, but it will factor to:
\n" ); document.write( "(t-36)(t+5) = 0
\n" ); document.write( ":
\n" ); document.write( "the positive solution
\n" ); document.write( "t = 36 days required by the 1st man
\n" ); document.write( "then
\n" ); document.write( "36 + 9 = 45 days required by the 2nd man
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check this
\n" ); document.write( "20/36 + 20/45
\n" ); document.write( ".56 + .44 = 1
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