document.write( "Question 503532: You have a wire that is 53 cm long. You wish to cut it into two pieces. One piece will be bent into the shape of a square. The other piece will be bent into the shape of a circle. Let A represent the total area of the square and the circle. What is the circumference of the circle when A is a minium?
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Algebra.Com's Answer #339364 by ankor@dixie-net.com(22740)\"\" \"About 
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You have a wire that is 53 cm long. You wish to cut it into two pieces.
\n" ); document.write( " One piece will be bent into the shape of a square. The other piece will be bent into the shape of a circle.
\n" ); document.write( " Let A represent the total area of the square and the circle.
\n" ); document.write( " What is the circumference of the circle when A is a minimum?
\n" ); document.write( ":
\n" ); document.write( "Let x = circumference of the circle
\n" ); document.write( "then
\n" ); document.write( "(53-x) = the perimeter of the square
\n" ); document.write( "and
\n" ); document.write( "\"%2853-x%29%2F4\" = the side of the square
\n" ); document.write( "and
\n" ); document.write( "\"%28%2853-x%29%2F4%29%5E2\" = the area of the square
\n" ); document.write( ":
\n" ); document.write( "Find the area of the circle using the circumference
\n" ); document.write( "find the radius (r)
\n" ); document.write( "2*pi*r = x
\n" ); document.write( "r = \"x%2F%282%2Api%29\"
\n" ); document.write( "r = \"x%2F6.28\"
\n" ); document.write( "Find the area of the circle
\n" ); document.write( "A = \"pi%2Ar%5E2\"
\n" ); document.write( "Replace r with \"x%2F6.28\"
\n" ); document.write( "A = \"pi\"*\"%28x%2F6.28%29%5E2\" = \"pi\"*\"%28x%5E2%2F39.48%29\"
\n" ); document.write( "cancel pi into 39.48
\n" ); document.write( "A = \"x%5E2%2F12.566\"
\n" ); document.write( "Total area of circle and square
\n" ); document.write( "A = \"x%5E2%2F12.566\" + \"%28%2853-x%29%2F4%29%5E2\" = \"x%5E2%2F12.566\" + \"%28%282809-106x%2Bx%5E2%29%2F16%29\"
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\n" ); document.write( "convert these fractions to decimal coefficients
\n" ); document.write( "A(x) = .0796x^2 + .0625x^2 - 6.625x + 175.5625
\n" ); document.write( "A(x) = .1421x^2 - 6.625x + 175.5625
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\n" ); document.write( "Find the axis of symmetry of this quadratic equation (min area)
\n" ); document.write( "x = \"%28-%28-6.625%29%29%2F%282%2A.1421%29\"
\n" ); document.write( "x = \"6.625%2F.2842\"
\n" ); document.write( "x = 23.31 cm is the circumference when they have min area
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