Question 975377
whats the standard form for x^2+y^2-4x+4y+7=0 and its center and radius?
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Complete the square for the x and y terms.
{{{x^2-4x + y^2+4y = -7}}}
{{{x^2-4x+4 + y^2+4y+4 = -7+4+4}}}
{{{(x-2)^2 + (y+2)^2 = 1}}}
--> center at (2,-2), r = 1
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The standard form,circle and radius for x^2+y^2+6y+7=0?
Do it the same way.