Question

How do you write an equation of a circle with center (-2, 1), radius = 4?

Answer 1

`(x+2)^2+(y-1)^2=16`

Explanation:

The standard equation of a circle with center `(a,b)` and radius `r` is given by

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

Then, given your problem,

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