Question

Which is the equation of a circle with center (0,1) and radius 2 units?

Answer 1

`x^2 + (y-1)^2 = 4`

Explanation:

Given: circle with center `(0, 1)` and `r = 2`

The standard equation for a circle is `(x - h)^2 + (y - k)^2 = r^`

where `"center" (h, k)` and `r = "radius"`

`(x-0)^2 + (y-1)^2 = 4`

Since `x-0 = x, " "x^2 + (y-1)^2 = 4`