document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=92075>Question 92075</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0395977258/algebrahomeworkh>algebra and trigonometry</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> can someone help me,i dont get this!!! Find the dimensions of a rectangle a with the greatest area whose perimeter is 30 feet. i dont get this!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66948 by </B><A HREF=/tutors/aboutme.mpl?userid=mathispowerful><B>mathispowerful(115)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathispowerful><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=66948\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  <BR>\n" );
document.write( "First there are more than one way to do it, since this is algebra.com, I will use quadratic equation to solve it.\r<BR>\n" );
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document.write( "Let x, y represent length and width of the rectangle.\r<BR>\n" );
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document.write( " then we have x+y = 15\r<BR>\n" );
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document.write( "we need to find maximum area, A. A = length times width = xy\r<BR>\n" );
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document.write( "from x+y = 15, y = 15 - x\r<BR>\n" );
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document.write( "in A=xy, substitute y by  15 - x\r<BR>\n" );
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document.write( "A = x(15 - x)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+15x+-x%5E2 ALIGN=MIDDLE  ALT=\"A+=+15x+-x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "this is a quadratic equation, the maximum value is at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x+=+-15%2F%282%2A%28-1%29%29 ALIGN=MIDDLE  ALT=\"+x+=+-15%2F%282%2A%28-1%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so x = 7.5, then y = 15 -x = 7.5\r<BR>\n" );
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document.write( "so it will be a square with length of 7.5 ft. <BR>\n" );
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