I interpret (-10,0) as being the centre of the circle. Standard form is (x+10)^2+y^2=a^2 where a is the radius.
If we put x=-2 and y=-3 we can find a^2: 8^2+9=a^2 so a^2=64+9=73 and we have the equation of the circle:
(x+10)^2+y^2=73 or (x+10)^2/73+y^2/73=1.