Answer:
90
Explanation:
The centre is (-2,9) so the first part of the equation will be (x+2)^2 + (y-9)^2 and to get the second half, you know the point on the circle which you can use to find the radius. So the triangle formed would be 3 long, 9 high and using Pythagoras you can do:

9+81=

90 =

and this equation ends with r^2 so you can substitute that back into the equation so together it will be
90