Answer:
[tex](x-9)^{2}+(y+4)^{2}=81[/tex]
Step-by-step explanation:
we know that
The equation of a circle in standard form is equal to
[tex](x-h)^{2}+(y-k)^{2}=r^{2}[/tex]
where
(h,k) is the center
r is the radius
In this problem we have
[tex](h,k)=(9,-4)[/tex]
[tex]r=9\ units[/tex]
substitute
[tex](x-9)^{2}+(y+4)^{2}=9^{2}[/tex]
[tex](x-9)^{2}+(y+4)^{2}=81[/tex] ----> equation of the circle in standard form
