Ellipse

An ellipse has 2 focus points. The sum of the distance from each of these two points to any point on the ellipse is constant.

The standard form is: x^{2}/a^{2} + y^{2}/b^{2} = 1

(For major axes along the x and y axes.)

Where a is the distance from the center of the ellipse to the outer edge along the x axis and b is the the distance from the center of the ellipse to the outer edge along the y axis.

EXAMPLE: Sketch 4x^{2} + 9y^{2} = 36

First we need to rearrange the equation into a form that looks like the standard form. How?

Divide the whole equation by 36.

We get:

x^{2}/9 + y^{2}/4 = 1

It