Find the center of the circle whose equation is x2 + y2 = 4.

The general equation of a circle is:

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

Where (a, b) represent the coordinates of the center and r is the radius.

Here in the equation:

X^2 + y^2 = 4

(x-0) ^2 + (y-0) ^2=2^2

Therefore, the circle has:

center - > (0,0)

Radius - > r=2