Question

This circle centered at the origin and the Length of its radius is 8. What is the equation of the circle?

Answer 1

D.....all ......dots are to make 20 wordt 

Answer 2

The equation of the circle is always:
$(x - h)^{2} + (y-k)^{2} = r^{2}$
Where (h, k) is the center of the circle, r is the radius. So, the equation will be:
$x^{2} + y^{2} = 64$
Hope this helps! The answer is B.