Question 769775
Complete the Squares for x and y to put the equation into standard form.  Then you can read (h,k) and radius value directly from the equation, and graph accordingly.


{{{x^2+y^2+8x-8y-49=0}}}
{{{x^2+8x+y^2-8y=49}}}
The square term for x is {{{(8/2)^2=16}}} and the square term for y is also 16.
{{{(x^2+8x+16)+(y^2-8y+16)=49+32}}}
{{{(x+4)^2+(y-4)^2=81}}}
{{{highlight((x+4)^2+(y-4)^2=9^2)}}}

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Center: (-4, 4)
Radius: 9 units
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