document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141301>Question 141301</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bob and Tom are mowing a yard which is 80' X 40'. They will each mow 1/2 of the yeard. They must mow the yeard in a spiral. How far in does Bob mow before turning it over to Tom? What equation is used to solve this? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102969 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=102969\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 80*40/2=(80-x)(40-x)<BR>\n" );
document.write( "3200/2=3200-120x+x^2<BR>\n" );
document.write( "1600=3200-120x+x^2<BR>\n" );
document.write( "x^2-120x+3200-1600=0<BR>\n" );
document.write( "x^2-120x+1600=0<BR>\n" );
document.write( "using the quadratic equation:<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-b%2B-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29 ALIGN=MIDDLE  ALT=\"x=%28-b%2B-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > we get:<BR>\n" );
document.write( "x=(120+-sqrt[-120^2-4*1*1600])/2*1 <BR>\n" );
document.write( "x=(120+-sqrt14,400-6,400])/2<BR>\n" );
document.write( "x=(120+-sqrt8,000)/2<BR>\n" );
document.write( "x=(120+-89.44)/2<BR>\n" );
document.write( "x=(120-89.44)/2<BR>\n" );
document.write( "x=30.56/2<BR>\n" );
document.write( "x=15.28' is the width of the mowed area that contains one half the total area.  </SPAN>\n" );
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