document.write( "Question 19912: This problem deals with a circle. Enter your answers as alebraic expressions in A, B, and C. Consider the equation
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\n" ); document.write( " $\"x%5E2%2By%5E2%2BAx%2BBy%2BC=0\"$ \r
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\n" ); document.write( "\n" ); document.write( "It describes a circle with center h,k and a radius r where \r
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Algebra.Com's Answer #9613 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
You need to get your equation into the standard form for a circle with center at (h, k) and radius r. $\"%28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2\"$ You can do this by completing the square in the x-terms and in the y-terms.\r
\n" ); document.write( "\n" ); document.write( " $\"x%5E2%2By%5E2%2BAx%2BBy%2BC=0\"$ Group the x-terms and the y-terms.
\n" ); document.write( " $\"%28x%5E2%2BAx%29+%2B+%28y%5E2%2BBy%29%2BC=0\"$ Now subtract C from both sides of the equation.
\n" ); document.write( " $\"%28x%5E2%2BAx%29+%2B+%28y%5E2%2BBy%29+=+-C\"$ Complete the square in the x-terms and in the y-terms.
\n" ); document.write( " $\"%28x%5E2%2BAx%2BA%5E2%2F4%29+%2B+%28y%5E2%2BBy%2BB%5E2%2F4%29+=+A%5E2%2F4+%2B+B%5E2%2F4+-+C\"$ Factor the x-group and the y-group and simplify.
\n" ); document.write( " $\"%28x%2BA%2F2%29%5E2+%2B+%28y%2BB%2F2%29%5E2+=+%28A%5E2%2BB%5E2-4C%29%2F4\"$ Compare this with:
\n" ); document.write( " $\"%28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"h+=+-A%2F2\"$
\n" ); document.write( " $\"k+=+-B%2F2\"$
\n" ); document.write( " $\"r+=+%281%2F2%29sqrt%28A%5E2%2BB%5E2-4C%29\"$
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