document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=891969>Question 891969</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One side of the rectangular field is bounded by a river. A farmer has 100m of fencing and wants to fence the other three sides of the field. If he wants to enclose an area of at least 800m^2, what will be the max. length of the field along the river. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #540176 by </B><A HREF=/tutors/aboutme.mpl?userid=LinnW><B>LinnW(1048)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=LinnW><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=LinnW><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=540176\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The dimensions of the enclosed area<BR>\n" );
document.write( "will be width x by length (100-2x).<BR>\n" );
document.write( "The length is reduced by the two ends<BR>\n" );
document.write( "of the rectangle.<BR>\n" );
document.write( "For an area of 800,<BR>\n" );
document.write( "x(100-2x) = 800<BR>\n" );
document.write( "100x - 2x^2 = 800<BR>\n" );
document.write( "add -800 to each side<BR>\n" );
document.write( "-2x^2 + 100x -800 = 0<BR>\n" );
document.write( "divide each side by -2<BR>\n" );
document.write( " x^2 -50x -400 = 0<BR>\n" );
document.write( "(x-10)(x-40) = 0<BR>\n" );
document.write( "So x = 10 or x = 40<BR>\n" );
document.write( "A value of x = 10 will produce the<BR>\n" );
document.write( "largest value for length along<BR>\n" );
document.write( "the river ( 100 - 2(10)) = 80 meters. </SPAN>\n" );
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