What is the center of the circle given by the equation (x−6)2+(y+3)2=72?
a. (-6, 3)
b. (-3, 6)
c. (6, -3)
d. (6, 7)

this coming off the top of my head but it's either C or A

none of the above.

for one of the equations to be used in the process, there has to be a term in the equation since squared is .

since there is only a term in the first equation, we cannot derive a from completing the square.

solving with completing the square