find the center and the radius of the circle

Question

How do I find the center and the radius of the circle

 

x^2+(y-3)^2=4

Answer 1

The general equation of a circle is:

(x-a)^2 + ( y-b)^2 = r^2

 

The center is (a,b) and the radius is r

 

In this case a=0 b = 3 r^2 = 4

 

center = (0, 3) and the radius is  2.