document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=118356>Question 118356</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Beginning witha fixed length of fence, a free-standing rectangular enclosure is built so that it encircles the maximum area. Show that this enclosure is actually a square. Remember that all squares are rectangles. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #86474 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=86474\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let 2k=\"length of fence\", y=\"length of enclosure\", x=\"width of enclosure\"\r<BR>\n" );
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document.write( "perimeter=2x+2y ___ 2k=2x+2y ___ k=x+y ___ k-y=x\r<BR>\n" );
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document.write( "area=x*y ___ a=(k-y)y ___ a=ky-y^2\r<BR>\n" );
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document.write( "the maximum area is at the axis of symmetry ___ y=-k/(2(-1)) ___ y=k/2\r<BR>\n" );
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document.write( "x+y=k ___ x+(k/2)=k ___ x=k/2\r<BR>\n" );
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document.write( "x=y ___ width=length ___ definition of square </SPAN>\n" );
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