Question

I am learning about ellipses and I want to know what are the foci and vertices. Are they always horizontal or vertical?

Answer 1

The foci and vertices aren't always horizontal or vertical. They're labelled in this picture pretty well:

http://sites.csn.edu/istewart/mathweb/Math127/ellipses/images/ellipse1.gif

and you can see that sometimes the ellipse can even be rotated like this! http://www.sensorsmag.com/files/sensor/nodes/2009/6475/Figure9.gif

So it doesn't even have to be either horizontal or vertical at all.

Answer 2

How do you know which side are the vertices and foci?

Answer 3

Are they the longer ends?

Answer 4

Yeah, the vertices and foci are on the longer ends, and they call that line they are on the Major Axis.

Answer 5

Ok thank you.