document.write( "Question 117007: find the radius\r
\n" ); document.write( "\n" ); document.write( "x^2-6x+y^2+4y = 36
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Algebra.Com's Answer #85078 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\"x%5E2-6x%2By%5E2%2B4y=36\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"%28-6%2F2%29%5E2=%28-3%29%5E2=9\" Take half of the x coefficient -6 and square it.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-6x%2B9%2By%5E2%2B4y=36%2B9\" Add this result to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-6x%2B9%2By%5E2%2B4y=45\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%284%2F2%29%5E2=%282%29%5E2=4\" Take half of the y coefficient 4 and square it.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-6x%2B9%2By%5E2%2B4y%2B4=45%2B4\" Add this result to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-6x%2B9%2By%5E2%2B4y%2B4=49\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-6x%2B9%29%2B%28y%5E2%2B4y%2B4%29=49\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-3%29%5E2%2B%28y%2B2%29%5E2=49\" Factor\r
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\n" ); document.write( "\n" ); document.write( "Since the general equation of a circle is\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "we can see that \"r%5E2=49\" with means \"r=7\". So the radius is 7
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