Question

How do you write the equation of the circle with center at (–6, 10) and diameter = 6?

Answer 1

`(x+6)^2 + (y-10)^2 = 9`

Explanation:

The equation of a circle of radius `(r)` centred at the point `(x_1, y_1)` is:

`(x-x_1)^2 + (y-y_1)^2 = r^2`

In this example: `x_1 = -6,` `y_1 = 10` and `r=6/2 =3`

Hence the equation of this circle is:
`(x+6)^2 + (y-10)^2 = 3^2`
`-> (x+6)^2 + (y-10)^2 = 9`