# How do you find the vertex, the directrix, the focus and eccentricity of: #(9x^2)/25 + (4y^2)/25 = 1#?

##### 1 Answer

Jun 16, 2017

Please see below.

#### Explanation:

This a typical equation of an ellipse centered at origin as it is of the form

As

Vertices, along major axis, are

and eccentricity given by

Focii, along

and the two directrix are

graph{(9x^2+4y^2-25)(x^2+(y-1.86)^2-0.005)(x^2+(y+1.86)^2-0.005)=0 [-5.02, 4.98, -2.36, 2.64]}