document.write( "Question 819410: What is the radius of the circle x^2+y^2+4x-4y-1=o \n" ); document.write( "

Algebra.Com's Answer #493086 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,\r
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document.write( "Standard Form of an Equation of a Circle is  
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document.write( "where Pt(h,k) is the center and r is the radius
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document.write( "x^2+y^2+4x-4y-1=o      |Completing square
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document.write( "(x+2)^2 - 4 + (y-2)^2 - 4 - 1 = 0
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document.write( "(x+2)^2  + (y-2)^2 = 9 
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document.write( "  r = 3 \n" );
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