document.write( "Question 792682: Under what conditions does the equation x^2 + y^2 + 2gx + 2fy +c = 0 represent a circle
\n" ); document.write( "1.with center on
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\n" ); document.write( "c) x and y axis \r
\n" ); document.write( "\n" ); document.write( "Can you please help me out? Thanks so much in advance:)
\n" ); document.write( "Can you also please show the steps it would really help me understand better:)
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Algebra.Com's Answer #480113 by josgarithmetic(39623)\"\" \"About 
You can put this solution on YOUR website!
Mostly a conic-section concept and symbolism exercise. First, you want to Complete-the-Square for the x and the y, and convert the equation to standard form. You will obtain something a little complicated, but you can use the formula.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+%2B+y%5E2+%2B+2gx+%2B+2fy+%2Bc+=+0\" as given.
\n" ); document.write( "\"x%5E2%2B2gx%2By%5E2%2B2fy%2Bc=0\"
\n" ); document.write( "The missing square term for x and for y are, in that order, \"%282g%2F2%29%5E2=g%5E2\" and \"%282f%2F2%29%5E2=f%5E2\". This will allow you to factor.
\n" ); document.write( "\"%28x%5E2%2B2gx%2Bg%5E2%29%2B%28y%5E2%2B2fy%2Bf%5E2%29%2Bc-g%5E2-f%5E2=0\"
\n" ); document.write( "\"highlight%28%28x%2Bg%29%5E2%2B%28y%2Bf%29%5E2=g%5E2%2Bf%5E2-c%29\"\r
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\n" ); document.write( "\n" ); document.write( "According to that standard form equation for a circle, the center is at (-g,-f) and the radius is \"sqrt%28g%5E2%2Bf%5E2-c%29\".\r
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\n" ); document.write( "\n" ); document.write( "You should now be able to work through to the necessary conclusions.
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