Question

1. Write the standard equation for a circle that has a center of (-5.-2) and a radius of 25.

Answer 1

`(x+5)^2+(y+2)^2=625`

Explanation:

The center-radius form a circle is
`(x-h)^2+(y-k)^2=r^2`. Okay, it is called standard form. But I like to call it center-radius form because it tells us the center (h,k) and the radius,r.

So we are given the following information r=25 and center=(h,k)=(-5,-2).

So we just plug this in like so:

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

`(x--5)^2+(y--2)^2=25^2`

`(x+5)^2+(y+2)^2=625`