Respuesta :

Answer:

x^2   +y^2 = 16    

Step-by-step explanation:

The equation of a circle is given by

(x-h) ^2 + (y-k)^2 = r^2  where (h,k) is the center and r is the radius

(x-0) ^2 + (y-0)^2 = 4^2

x^2   +y^2 = 16