Answer:
C.
Step-by-step explanation:
The equationof a circle:
[tex](x-h)^2+(y-k)^2=r^2[/tex]
(h, k) - center
r - radius
We have center = (4, -1) → h = 4, k = -1, and r = 9.
Substitute:
[tex](x-4)^2+(y-(-1))^2=9^2\\\\\huge\boxed{(x-4)^2+(y+1)^2=81}[/tex]
