document.write( "Question 403986: A wire 310 in. long is cut into two pieces. One piece is formed into a square and the other into a circle. If the two figures have the same area, what are the lengths of the two pieces of wire (to the nearest tenth of an inch)? \n" ); document.write( "
Algebra.Com's Answer #285638 by ankor@dixie-net.com(22740)\"\" \"About 
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A wire 310 in. long is cut into two pieces. One piece is formed into a square and the other into a circle.
\n" ); document.write( "If the two figures have the same area, what are the lengths of the two pieces of wire (to the nearest tenth of an inch)?
\n" ); document.write( ":
\n" ); document.write( "Let s = the side of the square
\n" ); document.write( "then
\n" ); document.write( "4s = the perimeter of the square
\n" ); document.write( "s^2 = the area of the square
\n" ); document.write( ":
\n" ); document.write( "Let r = the radius of the circle
\n" ); document.write( "then
\n" ); document.write( "\"2%2Api%2Ar\" = the circumference of the circle
\n" ); document.write( "\"pi%2Ar%5E2\" = area of the circle
\n" ); document.write( ":
\n" ); document.write( "\"the two figures have the same area,
\n" ); document.write( "s^2 = \"pi%2Ar%5E2\"
\n" ); document.write( "s = \"sqrt%28pi%2Ar%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( ":
\n" ); document.write( "\"A wire 310 in. long is cut into two pieces.\"
\n" ); document.write( ":
\n" ); document.write( "Perimeter + Circumference = 310 inches
\n" ); document.write( "4s + \"2%2Api%2Ar\" = 310
\n" ); document.write( ":
\n" ); document.write( "Replace s with \"sqrt%28pi%2Ar%5E2%29\"
\n" ); document.write( "\"4%28sqrt%28pi%2Ar%5E2%29%29+%2B+%282%2Api%2Ar%29\" = 310
\n" ); document.write( ":
\n" ); document.write( "simplify, divide by 2, Extract r
\n" ); document.write( "\"2r%28sqrt%28pi%29%29+%2B+%28pi%2Ar%29\" = 155
\n" ); document.write( ":
\n" ); document.write( "Change pi to decimal values
\n" ); document.write( "2r(1.772) + r(3.1416) = 155
\n" ); document.write( "3.545r + 3.1416r = 155
\n" ); document.write( "6.6865r = 155
\n" ); document.write( "r = \"155%2F6.6865\"
\n" ); document.write( "r = 23.18
\n" ); document.write( ":
\n" ); document.write( "Find the circumference
\n" ); document.write( "C = \"2%2Api%2A23.18\"
\n" ); document.write( "C = 145.7 inches the length of the wire to make the circle
\n" ); document.write( "then
\n" ); document.write( "310 - 145.7 = 164.3 inches is the length to make the square
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\n" ); document.write( "Check this by finding the area of circle and the square
\n" ); document.write( "Square: (164.3/4)^2 = 1687.155 sq/inches
\n" ); document.write( "Circle: \"pi%2A23.18%5E2\" = 1688.0 sq/inches, discrepancy is from rounding off\r
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