document.write( "Question 136438: find the center and radius of the circle given by:
\n" ); document.write( "x^2+10x+y^2+12y=-12 \n" ); document.write( "

Algebra.Com's Answer #99933 by Earlsdon(6294) $\"\"$ $\"About$

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The general form for a circle with center at (h, k) and radius r is:
\n" ); document.write( " $\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2\"$
\n" ); document.write( "In your equation:
\n" ); document.write( " $\"x%5E2%2B10x%2By%5E2%2B12y+=+-12\"$ First complete the squares in the x-terms and in the y-terms.
\n" ); document.write( " $\"%28x%5E2%2B10x%2B25%29%2B%28y%5E2%2B12y%2B36%29+=+25%2B36-12\"$ Factor the left side and simplify the right side.
\n" ); document.write( " $\"%28x%2B5%29%5E2+%2B+%28y%2B6%29%5E2+=+48\"$ Compare this with the general form:
\n" ); document.write( " $\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2\"$
\n" ); document.write( " $\"h+=+-5\"$ , $\"k+=+-6\"$ , and $\"r+=+sqrt%2848%29\"$
\n" ); document.write( "Center is at: (-5, -6) and the radius is, $\"r+=+4sqrt%283%29\"$ \n" ); document.write( "

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