document.write( "Question 42205This question is from textbook college algebra gary rockswold
\n" ); document.write( ": Could someone please help me with this Thanks!!!!!!!\r
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\n" ); document.write( "\n" ); document.write( ") John has 300 feet of lumber to frame a rectangular patio (the perimeter of a rectangle is 2 times length plus 2 times width). He wants to maximize the area of his patio (area of a rectangle is length times width). What should the dimensions of the patio be, and show how the maximum area of the patio is calculated from the algebraic equation.
\n" ); document.write( "Show clearly the algebraic steps which prove your dimensions are the maximum area which can be obtained.
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Algebra.Com's Answer #27365 by psbhowmick(878)\"\" \"About 
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Let length = L ft, width = W ft.
\n" ); document.write( "Then perimeter = 300 = 2(L + W)
\n" ); document.write( "or L + W =150 _____(1)\r
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\n" ); document.write( "\n" ); document.write( "Now, area is given by
\n" ); document.write( "A = W x L
\n" ); document.write( "= (150 - L) x L
\n" ); document.write( "= \"150L+-+L%5E2\"
\n" ); document.write( "= \"75%5E2+-+%28L%5E2+-+2%2AL%2A75+%2B+75%5E2%29\"
\n" ); document.write( "or \"A+=+75%5E2+-+%28L+-+75%29%5E2\"________(2)\r
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\n" ); document.write( "\n" ); document.write( "For 'A' to be maximum, \"%28L+-+75%29%5E2\" has to be minimum.
\n" ); document.write( "But it is a real square and hence cannot be negative.
\n" ); document.write( "So its minimum value is zero.
\n" ); document.write( "So, \"%28L+-+75%29%5E2+=+0\"
\n" ); document.write( "or L = 75\r
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\n" ); document.write( "\n" ); document.write( "We have obtained L = 75. Putting this value in (1) we find W = 75.\r
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\n" ); document.write( "\n" ); document.write( "Putting L = 75 in (2) we will get the maximum value of 'A'.
\n" ); document.write( "A\"%28max%29+=+75%5E2+-+%2875+-+75%29%5E2+=+75%5E2\" = 5625\r
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\n" ); document.write( "\n" ); document.write( "So the maximum area of the patio is 5625 sq ft and its dimensions are 75 ft x 75 ft. In other words for maximum area, the patio is a square with side 75 ft.
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