document.write( "Question 1040615: A rectangular pen has twelve enclosures. If you have 1,000 feet, what is the maximum area that can be enclosed \n" ); document.write( "
Algebra.Com's Answer #655465 by Boreal(15235)\"\" \"About 
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If you have 3 enclosures, you need 4 sets of fencing per pen. So for 12 enclosures, you need 13 sets.
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\n" ); document.write( "Let the length= L
\n" ); document.write( "13L fence is needed.
\n" ); document.write( "The width is (1000-13L)/2, because there are two widths.
\n" ); document.write( "The area is maximized
\n" ); document.write( "L*(1000-13L)/2
\n" ); document.write( "500L-(13L/2) is fence used
\n" ); document.write( "Take the derivative and set it equal to 0.
\n" ); document.write( "500-13L=0
\n" ); document.write( "13L=500
\n" ); document.write( "L=38.46 feet.
\n" ); document.write( "The width is 250 feet.
\n" ); document.write( "Twice 250 is 500 feet of fence for both widths.
\n" ); document.write( "13L=500 feet.
\n" ); document.write( "The area is 500*250=125,000ft^2
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\n" ); document.write( "Check using 40 feet of fencing for enclosure. The area should be a little less.
\n" ); document.write( "That is 520 feet length and 240 feet width. Area is 124,800 sq ft.
\n" ); document.write( "Typically these problems either turn out to be squares or rectangles where the width is half the length. \n" ); document.write( "
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