What is the equation of this circle in general form?

A. x2+y2−2x−6y+4=0

B. x² + y² + 2x + 6y + 4 = 0

C. x2+y2−2x−6y−26=0

D. x2+y2+2x+6y−26=0

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1 Answer
May 11, 2017

The equation of the circle is #x^2+y^2-2x-6y-26=0#

Explanation:

We need

#(a-b)^2=a^2-2ab+b^2#

The equation of a circle and radius #=r# is

#(x-h)^2+(y-h)^2=r^2#

Here, the center is #(1,3)# and the radius is #=6#

The equation of the circle is

#(x-1)^2+(y-3)^2=36#

#x^2-2x+1+y^2-6y+9-36=0#

#x^2+y^2-2x-6y-26=0#