document.write( "Question 909877: Working together, Angel and Sheila painted a fence in 8 hours. Last year, Sheila painted the fence by herself. the year before, Angel painted it by herself, but it took 12 hours less than Sheila took. how long did Angel and Sheila take, when each was painting alone? \n" ); document.write( "
Algebra.Com's Answer #552096 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
1/x+1/(x+12)=1/8
\n" ); document.write( "(8*x*(x+12))/x+(8*x*(x+12))/(x+12)=(8*x*(x+12))/8
\n" ); document.write( "(8*(x+12))+8*x=x*(x+12)
\n" ); document.write( "8*x+96+8*x=x^2+12*x
\n" ); document.write( "16*x+96=x^2+12*x
\n" ); document.write( "x^2-4*x-96=0
\n" ); document.write( "x^2-4*x=96
\n" ); document.write( "add it
\n" ); document.write( "x^2-4*x+(-4/2)=96+(-4/2)
\n" ); document.write( "square it
\n" ); document.write( "x^2-4*x+(16/4)=96+(16/4)
\n" ); document.write( "x^2-4*x+(4)=96+(4)
\n" ); document.write( "x^2-4*x+(4)=100
\n" ); document.write( "(x-2)^2=100
\n" ); document.write( "(x-2)^2=100
\n" ); document.write( "we can continue
\n" ); document.write( "x-2=+-10.0
\n" ); document.write( "x=2+-10.0
\n" ); document.write( "Positive useful answer:
\n" ); document.write( "x=2+10.0
\n" ); document.write( "One answer is x=12
\n" ); document.write( "x+12=12+12
\n" ); document.write( "x+12=24
\n" ); document.write( "check
\n" ); document.write( "1/x+1/(x+12)=1/8
\n" ); document.write( "1/12+1/(12+12)=1/8
\n" ); document.write( "1/12+1/24=1/8
\n" ); document.write( "2/23+1/24=3/24
\n" ); document.write( "3/24=3/24
\n" ); document.write( "ok\r
\n" ); document.write( "\n" ); document.write( "Useless answer:
\n" ); document.write( "x=2-10.0
\n" ); document.write( "Useless answer is x=-8.0
\n" ); document.write( " x =-8.0
\n" ); document.write( " This answer is useless because it is Negative
\n" ); document.write( "For real life cases involving time, distance and other measurements, we reject the negative results
\n" ); document.write( " \n" ); document.write( "
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