Question

What is the center and radius of the circle with equation `(x+3)^2 + (y+8)^2=49`?

Answer 1

Center is at `(-3,-8)` Radius is `7` units

Explanation:

The equation of a circle of radius r centered at the point `(a,b)` is:

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

In this example `a = -3 and b=-8`
Therefore the circle is centered at the point `(-3, -8)`

Also in the example `r^2 = 49`
`r = sqrt(49)`
`r = 7` (Since `r>0`)