document.write( "Question 199521: A regular storage area is to be constructed along the side of a tall building. A security fence is required along the remaining three sides of the area. What is the maximum area that can be enclosed with 800m of fencing? \n" ); document.write( "
Algebra.Com's Answer #150273 by ankor@dixie-net.com(22740)\"\" \"About 
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A regular storage area is to be constructed along the side of a tall building.
\n" ); document.write( " A security fence is required along the remaining three sides of the area.
\n" ); document.write( " What is the maximum area that can be enclosed with 800m of fencing?
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\n" ); document.write( "Let x = width of the fenced area
\n" ); document.write( "let L = length
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\n" ); document.write( "Perimeter with 3 sides:
\n" ); document.write( "L + 2x = 800
\n" ); document.write( "L = (800-2x)
\n" ); document.write( ":
\n" ); document.write( "Area = x * L
\n" ); document.write( "Replace L with (800-2x)\r
\n" ); document.write( "\n" ); document.write( "A = x(800-2x)
\n" ); document.write( "A = -2x^2 + 800x
\n" ); document.write( ":
\n" ); document.write( "Find the max area by finding the axis of symmetry: x = -b/2a
\n" ); document.write( "In this equation a=-2; b= 800
\n" ); document.write( "x = \"%28-800%29%2F%282%2A-2%29\"
\n" ); document.write( "x = \"%28-800%29%2F%28-4%29\"
\n" ); document.write( "x = +200 m, width for max area
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\n" ); document.write( "Find max area, x=200
\n" ); document.write( "A = -2(200^2) + 800(200)
\n" ); document.write( "A = -2(40000) + 160000
\n" ); document.write( "A = -80000 + 160000
\n" ); document.write( "A = 80,000 sq/meters is max area
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