document.write( "Question 1117326: show that the radius of a semicircle whose perimeter is numerically equal to its area is
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Algebra.Com's Answer #732367 by Theo(13342)\"\" \"About 
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the circumference of a circle is equal to 2 * pi * r\r
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\n" ); document.write( "\n" ); document.write( "the circumference of half a circle is equal to pi * r + 2 * r.\r
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\n" ); document.write( "\n" ); document.write( "you are talking about half the circumference of the circle plus the length of the diagonal which is equal to 2 * r.\r
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\n" ); document.write( "\n" ); document.write( "the area of the circle is equal to pi * r^2.\r
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\n" ); document.write( "\n" ); document.write( "the area of half the circle is equal to pi * r^2 / 2\r
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\n" ); document.write( "\n" ); document.write( "if the circumference of half the circle is equal to the area of half the circle, then:\r
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\n" ); document.write( "\n" ); document.write( "pi * r + 2 * r = pi * r^2 / 2\r
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\n" ); document.write( "\n" ); document.write( "multiply both sides of this equation by 2 to get:\r
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\n" ); document.write( "\n" ); document.write( "2 * pi * r + 4 * r = pi * r^2\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by r to get:\r
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\n" ); document.write( "\n" ); document.write( "2 * pi + 4 = pi * r\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by pi to get:\r
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\n" ); document.write( "\n" ); document.write( "(2 * pi + 4) / pi = r\r
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\n" ); document.write( "\n" ); document.write( "that's your solution.\r
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\n" ); document.write( "\n" ); document.write( "you have r = (2 * pi + 4) / pi.\r
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\n" ); document.write( "\n" ); document.write( "this is the same as what you are showing, except that you needed to put parentheses around 2pi + 4.\r
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\n" ); document.write( "\n" ); document.write( "what you are showing as 2π+4/π should be (2π+4)/π\r
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