document.write( "Question 807560: Write the equation of a circle with center at the origin and radius 7. \n" ); document.write( "
Algebra.Com's Answer #486374 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Use the fact that\r\n" );
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document.write( "(x-h)² + (y-k)² = r² is the equation of a circle,\r\n" );
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document.write( "where (h,k) = the center and r = the radius.\r\n" );
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document.write( "In your problem,\r\n" );
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document.write( "origin = (0,0) and so h=0 and k=0  and radius = r = 7.\r\n" );
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document.write( "(x-0)² + (y-0)² = 7²\r\n" );
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document.write( "which simplifies to\r\n" );
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document.write( "x² + y² = 49\r\n" );
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document.write( "Edwin
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