Question

How do you find the center and radius of `(x – 9)^2 + y^2 = 484`?

Answer 1

`(9, 0)` is the center and `22` is radius.

Explanation:

Equation of a circle with center at `()a, b)` and radius `r` can be expressed as

`(x-a)^2+(y-b)^2=r^2`, as any point `(x,y)` will be at a distance of `r` from center at `(a,b)`.

As the equation `(x–9)^2+y^2=484` can be written as

`(x–9)^2+(y-o)^2=22^2`

It is obvious from the equation that

`(9, 0)` is the center and `22` is radius.