document.write( "Question 958223: Find the dimensions that produce the maximum floor area for a one-story house that is rectangular in shape and has a perimeter of 151ft
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Algebra.Com's Answer #585633 by LinnW(1048)\"\" \"About 
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perimeter = 2 * length + 2 * width
\n" ); document.write( "set L = length , W = width
\n" ); document.write( "perimeter = 2L + 2W
\n" ); document.write( "since perimeter is to be 151
\n" ); document.write( "151 = 2L + 2W
\n" ); document.write( "Solving for L,
\n" ); document.write( "151 - 2W = 2L
\n" ); document.write( "dividing each side by2
\n" ); document.write( "\"%28151+-+2W%29%2F2+=+2L%2F2\"
\n" ); document.write( "\"%28151+-+2W%29%2F2+=+L\"
\n" ); document.write( "Since area = L*W
\n" ); document.write( "\"+area+=+%28%28151+-+2W%29%2F2%29+%2A+W+\"
\n" ); document.write( "\"+area+=+%28151W+-+2W%5E2%29%2F2+\"
\n" ); document.write( "multiplying each side by 2
\n" ); document.write( "\"+2+%2A+area+=+%28151W+-+2W%5E2%29+\"
\n" ); document.write( "set y = 2*area
\n" ); document.write( "If we maximize the value of y in the equation
\n" ); document.write( "\"+y+=+%28151W+-+2W%5E2%29+\"
\n" ); document.write( "we will can determine the best dimensions for L and W
\n" ); document.write( "rewriting
\n" ); document.write( "\"+y+=+-2W%5E2+%2B+151W+\"
\n" ); document.write( "Using the coordinate values a = -2 and b = 151
\n" ); document.write( "the value of W where y is maximum occurs when -b/2a is the value of W.
\n" ); document.write( "\"-b%2F2a+=+-%28151%2F2%28-2%29%29\"
\n" ); document.write( "\"-b%2F2a+=+151%2F4\"
\n" ); document.write( "area will be maximum when W = 151/4
\n" ); document.write( "We previously determined \"+L+=+%28151-2W%29%2F2+\" so substituting we get
\n" ); document.write( "\"+L+=+%28151-2%28151%2F4%29%29%2F2+\"
\n" ); document.write( "\"+L+=+%28151-%28151%2F2%29%29%2F2+\"
\n" ); document.write( "\"+L+=+%28151%2F2%29%2F2+\"
\n" ); document.write( "\"+L+=+151%2F4+\"
\n" ); document.write( "So the maximum area will occur when W = 151/4 and L = 151/4
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