document.write( "Question 405566: A Norman window has the shape of a rectangle surmounted by a semicircle. If the perimeter of the window is 36 ft, express the area A of the window as a function of the width x of the window.
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Algebra.Com's Answer #286470 by ankor@dixie-net.com(22740)\"\" \"About 
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A Norman window has the shape of a rectangle surmounted by a semicircle.
\n" ); document.write( " If the perimeter of the window is 36 ft, express the area A of the window as
\n" ); document.write( " a function of the width x of the window.
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\n" ); document.write( "Let x = the width of the window and diameter of the semicircle
\n" ); document.write( "Let h = height of the rectangular portion of the window
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\n" ); document.write( "Perimeter:
\n" ); document.write( "twice the height + the width + half the circumference = 36 ft
\n" ); document.write( "2h + x + .5x*pi = 36
\n" ); document.write( "2h + x + 1.57x = 36; convert pi to a decimal value * .5
\n" ); document.write( "2h + 2.57x = 36;
\n" ); document.write( "2h = 36 - 2.57x
\n" ); document.write( "h = \"%28%2836-2.57x%29%29%2F2\"
\n" ); document.write( "h = (18-1.285x)
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\n" ); document.write( "Area = semicircle + rectangle
\n" ); document.write( "Radius = .5x
\n" ); document.write( "A = (.5*pi*(.5x)^2) + (x*h)
\n" ); document.write( "Convert pi to a decimal value times .5; Replace h with (18-1.285x
\n" ); document.write( "A = (1.57*.25x^2) + x(18-1.285x)
\n" ); document.write( "A = .3927x^2 - 1.285x^2 + 18x
\n" ); document.write( "A = -.8923x^2 + 18x\r
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