Question

How do you write an equation for a circle with center (5,5) with a radius of 7?

Answer 1

`(x-5)^2+(y-5)^2=7^2`

Explanation:

The equation of a circle with centre `(h, k)` and radius `r` can be written:

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

So in our example, the equation of the circle can be written:

`(x-5)^2+(y-5)^2=7^2`

graph{((x-5)^2+(y-5)^2-7^2)((x-5)^2+(y-5)^2-0.04)=0 [-18.09, 21.91, -5.76, 14.24]}