# How do you find the equation given center passes through the origin and has its center at (0,4)?

##### 1 Answer

Dec 23, 2016

#### Explanation:

Assuming this is to be the equation of a circle (although it was asked under the more general "Geometry of an Ellipse")

A circle with center

If the required circle has its center at

then

and

Further if its center is at

So the equation of the required circle must be

or, simplifying slightly: