Question

How do you find the center and radius of the circle `x^2+y^2=4`?

Answer 1

center `(0,0)`
Radius `=2`

Explanation:

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`