The standard equation for a circle is `(x-h)^2+(y-k)^2=r^2` where (h,k) is the center of the circle, and r is the radius.

Given `x^2+y^2=49` we could write as `(x-0)^2+(y-0)^2=7^2` **so the center is at the origin (0,0) and the radius is 7.**

The standard equation for a circle is `(x-h)^2+(y-k)^2=r^2` where (h,k) is the center of the circle, and r is the radius.

Given `x^2+y^2=49` we could write as `(x-0)^2+(y-0)^2=7^2` **so the center is at the origin (0,0) and the radius is 7.**