Question

A circle has the equation `(x+1)^2+(y-3)^2=16`. What are the coordinates of its center and length of its radius?

Answer 1

The center is `C=(-1;3)` the radius is `r=4`

Explanation:

The equation is in form of `(x-a)^2+(y-b)^2=r^2`, so the coordinates and the radius are:

`C=(a,b)`, radius `r`