# Find equation of circle whose radius is 3 and center is origin??

##### 1 Answer

Feb 22, 2018

#### Explanation:

The general equation of a circle is:

We want a circle with an a center

Therefore

We also want a radius

Given these values, we can substitute into our equation to get:

Simplify and we get the equation:

This is the equation we want and its graph looks like

graph{x^2+y^2=9 [-10, 10, -5, 5]}