document.write( "Question 244635: Find the center and the radius of the circle described by the equation\r
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Algebra.Com's Answer #178893 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Find the center and the radius of the circle described by the equation \r\n" );
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document.write( "Get the term in  next to the term in \r\n" );
document.write( "Get the term in  next to the term in \r\n" );
document.write( "Add  to both sides to get the constant on the right:\r\n" );
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document.write( "Multiply the coefficient of , which is  by ,\r\n" );
document.write( "getting . Then square , getting .  Then add \r\n" );
document.write( " to both sides, writing it next to the term in  on\r\n" );
document.write( "the left.\r\n" );
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document.write( "Multiply the coefficient of , which is  by ,\r\n" );
document.write( "getting . Then square , getting .  Then add \r\n" );
document.write( " to both sides, writing it next to the term in  on\r\n" );
document.write( "the left.\r\n" );
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document.write( "Factor the first three terms on the left as a perfect square:\r\n" );
document.write( "Factor the last three terms on the left as a perfect square:\r\n" );
document.write( "Combine the numbers on the right side:\r\n" );
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document.write( "Compare that to the standard equation of a circle, which is:\r\n" );
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document.write( "where the center is \r\n" );
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document.write( "So , , \r\n" );
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document.write( "Therefore the center is the point \r\n" );
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document.write( "And since \r\n" );
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document.write( ", we take the square root of both sides, \r\n" );
document.write( "and get\r\n" );
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document.write( "So the radius of the circle is .\r\n" );
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document.write( "Edwin

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