document.write( "Question 812370: The sides of a square are 8 cm. find the circumference of the circumscribed circle. \n" ); document.write( "
Algebra.Com's Answer #489134 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Draw a diagonal of the square (in green):\r\n" );
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document.write( "That green diagonal is a diameter of the circle, and its length can\r\n" );
document.write( "be calculated using the Pythagorean theorm on the right triangle which\r\n" );
document.write( "is the lower half of that square.\r\n" );
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document.write( "a² + b² = c²\r\n" );
document.write( "8² + 8² = c²\r\n" );
document.write( "64 + 64 = c²\r\n" );
document.write( "    128 = c²\r\n" );
document.write( "   √128 = c\r\n" );
document.write( "  √64·2 = c\r\n" );
document.write( "    8√2 = c\r\n" );
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document.write( "So the diameter of the circle is 8√2cm\r\n" );
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document.write( "The formula for the circumference of a circle is\r\n" );
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document.write( "C = pd where d is the diameter.\r\n" );
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document.write( "C = p·8√2\r\n" );
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document.write( "C = 8p√2.\r\n" );
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document.write( "That's approximately 35.543 cm.\r\n" );
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document.write( "Edwin
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