Question

How do you find the center and radius of the circle: `(x - 6)^2 + y^2 = 49`?

Answer 1

Slightly reformulate in standard form to find that the centre is at `(6, 0)` and radius `7`.

Explanation:

This equation is essentially the same as:

`(x-6)^2+(y-0)^2 = 7^2`

which is in the standard form:

`(x-h)^2+(y-k)^2 = r^2`

... the equation of a circle with centre `(h, k)` and radius `r`.

So the centre of our example circle is `(6, 0)` and radius `7`.