Question

Write an equation of the circle with center (-4, -9) and diameter 10.

Answer 1

`(x+4)^2+(y+9)^2=25`

Explanation:

The equation of a circle with center (h,k) and radius r is

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

You are given (h,k)=(-4,-9) and the radius=(diameter)/2=10/2=5.

Plug in the information and you will have your equation:

`(x-(-4))^2+(y-(-9))^2=(5)^2`.

Simplify: