document.write( "Question 644417: A and B can finish the job in 6 days. A can work 5 days less than B. Find the number of days it would take each working alone to finish the job. \n" ); document.write( "
Algebra.Com's Answer #405094 by ankor@dixie-net.com(22740)\"\" \"About 
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A and B can finish the job in 6 days.
\n" ); document.write( " A can work 5 days less than B.
\n" ); document.write( " Find the number of days it would take each working alone to finish the job.
\n" ); document.write( ":
\n" ); document.write( "Let a = time required by a working alone
\n" ); document.write( "then
\n" ); document.write( "(a+5) = time required by b working alone
\n" ); document.write( "Let the completed job = 1
\n" ); document.write( ":
\n" ); document.write( "\"6%2Fa\" + \"6%2F%28%28a%2B5%29%29\" = 1
\n" ); document.write( "multiply by a(a+5)
\n" ); document.write( "a(a+5)*\"6%2Fa\" + a(a+5)*\"6%2F%28%28a%2B5%29%29\" = a(a+5)
\n" ); document.write( "cancel out the denominators
\n" ); document.write( "6(a+5) + 6a = a(a+5)
\n" ); document.write( "6a + 30 + 6a = a^2 + 5a
\n" ); document.write( "combine on the right
\n" ); document.write( "0 = a^2 + 5a - 12a - 30
\n" ); document.write( "A quadratic equation
\n" ); document.write( "a^2 - 7a - 30 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(a-10)(a+3) = 0
\n" ); document.write( "The positive solution is all we want here
\n" ); document.write( "a = 10 hrs A's time working alone
\n" ); document.write( "then, obviously
\n" ); document.write( "B requires 15 hrs working alone
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