Question

How do you write an equation for a circle with center (5, -4) and radius 11?

Answer 1

`(x-5)^2+(y+4)^2=121`

Explanation:

Any circle centred at `(a,b)` and with radius `r` has equation
`(x-a)^2+(y-b)^2=r^2`.

So in this particular case the equation will be

`(x-5)^2+(y+4)^2=121`