You didn't give us the equation, but circle equations are in the form;
(x-h)^2 + (y-k)^2 =r^2 where h and k are the x and y coordinate of the center and r is the radius of the circle squared. 
        
             
        
        
        
Answer:
0.81241
if i'm wrong i'm rlly rlly sorry!!
 
        
             
        
        
        
Its upsidedown, witch one do you need help with?
 
        
             
        
        
        
Answer:
D
Step-by-step explanation: