Question

Given `(x+10)^2+(y-3)^2=121` what is the radius of this circle?

Answer 1

The radius of the circle is `11`

Explanation:

In the equation of a circle:

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

you can write that:

• the radius of the circle is `r`
• the circle's center has coordinates: `(a,b)`

So in your equation the radius is `sqrt(121)=11` and the centre is `(-10;3)`