Answer:
5
Step-by-step explanation:
The radius is 5.
All I do was think of the center-radius form a circle
(x-h)^2+(y-k)^2=r^2
x^2 + y^2 =25
(x-0)^2+(y-0)^2=5^2
The center is (0,0) and the radius is 5.
So a point on the circle (x,y) has a distance of 5 from the center
and the center's case here is (0,0).
