## peekaboopork 2 years ago HEEELPPP!!!!Give the equation of the circle with the radius 5 whose center is the the origin.

1. richyw

the equation for a circle centered at the point $$(a,b)$$ with radius $$r$$ is$(x-a)^2 + (y-b)^2 = r^2$

2. richyw

and you know it is at the origin, so you have $$a,b$$ and $$r$$. Just plug it in!

3. richyw

Or in polar coordinates you can just say $$r(\theta)=5$$