Question

What the center of
X^2+(y+3)=9

Answer 1

Assuming you mean
`x^2+(y+3)^2=9`, which is the equation of a circle :

the general equation of a circle of radius
`R` and center
`(a,b)` is
`(x-a)^2+(y-b)^2=R^2` hence here the center is
`\boxed{(0,-3)}`