Question 185749
Circle whose center is at (h,k)
(Called the "center-radius form")

(x - h)^2 + (y - k)^2 = r^2

You were given (x+1) + (y-5)^2 = 4....Are you sure the first quantity is not squared?

If we take the square root of 4, we get our radius to be 2.

To find the circumference of a circle, we use the formula C = pid, where C = circumference and d = diameter.

Well, it takes two radii to make 1 diameter.

Our diameter is found by using d = 2r.

I found the radius to be 2.

Before we can apply the circumference formula, we must find the diameter.

So, d = 2(2) = 4.

C = pi(4), where pi = 3.14

C = (3.14)(4)

Can you finish now?  Simply multiply to find C.

Is this what you were looking for?