The equation of the circle:
[tex](x-x_0)^2+(y-y_0)^2=R^2[/tex]
[tex]x_0=-6;y_0=-3; R=12,so\\(x-(-6))^2+(y-(-3))^2=12^2\\(x+6)^2+(y+3)^2=144[/tex]
Answer: [tex](x+6)^2+(y+3)^2=144[/tex]