document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=782510>Question 782510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It takes red 9 hours longer than Hannah to build a stone wall. Working together, they can build the wall in 20 hours. How long would it take each, working alone, to build the wall? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #476408 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=476408\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let Hannah take x hours<BR>\n" );
document.write( "she does 1/x of job in 1 hour\r<BR>\n" );
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document.write( "Red takes x+9 hours<BR>\n" );
document.write( "so he does   1/(x+9) of the job in 1 hour\r<BR>\n" );
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document.write( "In 1 hour they do\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2Fx%29+%2B+1%2F%28x%2B9%29 ALIGN=MIDDLE  ALT=\"%281%2Fx%29+%2B+1%2F%28x%2B9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > of the job in 1 hour\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2Fx%29+%2B+1%2F%28x%2B9%29 ALIGN=MIDDLE  ALT=\"%281%2Fx%29+%2B+1%2F%28x%2B9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > =1/20\r<BR>\n" );
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document.write( "multiply by 20x(x+9)\r<BR>\n" );
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document.write( "20(x+9)+20x=x(x+9)\r<BR>\n" );
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document.write( "20x+180+20x=x^2+9x\r<BR>\n" );
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document.write( "x^2+9x-40x-180=0\r<BR>\n" );
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document.write( "x^2-31x-180=0\r<BR>\n" );
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document.write( "x^2-36x+5x-180=0\r<BR>\n" );
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document.write( "x(x-36)+5(x-36)=0\r<BR>\n" );
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document.write( "(x-36)(x+5)=0\r<BR>\n" );
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document.write( "x=36 OR x=-5<BR>\n" );
document.write( "ignore negative\r<BR>\n" );
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document.write( "Hannah does it in 36 hours\r<BR>\n" );
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document.write( "Red does it 45 hours  (36+9) </SPAN>\n" );
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