document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=166708>Question 166708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the dimensions of a rectangle (a) with the greatest area whose perimeter is 30 feet. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122851 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=122851\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the dimensions of a rectangle (a) with the greatest area whose perimeter is 30 feet.<BR>\n" );
document.write( "Area = Length * Width<BR>\n" );
document.write( "Perimeter = 2L + 2W = 30<BR>\n" );
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document.write( "L+W = 15<BR>\n" );
document.write( "W = 15-L<BR>\n" );
document.write( "Area = L*W = L*(15-L) <BR>\n" );
document.write( "A = 15L - L^2<BR>\n" );
document.write( "To find the maximum, set the 1st derivative to zero<BR>\n" );
document.write( "15 - 2L = 0<BR>\n" );
document.write( "L = 7.5<BR>\n" );
document.write( "W = 7.5<BR>\n" );
document.write( "The max area for a rectangle is a square, always.  The max area for a given perimeter is a circle. </SPAN>\n" );
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