document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=597839>Question 597839</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You want to form a rectangular pen of area, a=70 ft^2. One side of the pen is to be formed by an existing building and the other three sides by a fence. If w is the width of the sides of the rectangle perpendicular to the building, then the length of the side parallel to the building is L=70/w. The total amount of fence required is the function F=2w + 70/w, in feet. \r<BR>\n" );
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document.write( "Determine the dimensions of the rectangle that requires a minimum amount of fence. Round to decimal places.<BR>\n" );
document.write( "width =         feet<BR>\n" );
document.write( "length =        feet\r<BR>\n" );
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document.write( "I have been having difficulty with area problems. Any help would be greatly appreciated. Thanks!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #378586 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=378586\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Using calculus is one way to solve the problem, and is probably the most common way. It is also possible to solve this one without calculus.\r<BR>\n" );
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document.write( "If you know the AM-GM (arithmetic mean-geometric mean) inequality, you can say that\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \frac{2w + \frac{70}{w}}{2} \ge \sqrt{2w(\frac{70}{w})}\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \frac{2w + \frac{70}{w}}{2} \ge \sqrt{140}\">\r<BR>\n" );
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document.write( "By AM-GM, equality occurs if and only if <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE 2w = \frac{70}{w} \Rightarrow w = \sqrt{35}\">. </SPAN>\n" );
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