Help in Euclidean geometry

Hi Kayla Murray,

In geometry, coplanar means the points all lie on the same plane.

Collinear means the points are all on the same line. If points are collinear, they can't be coplanar.

A simple way of finding out if points are coplanar or collinear is by seeing if you can draw a plane or line through them. 

I have been wondering the same thing. On the video that Sal was talking about collinear lines, it was just explaining how to do it when the points on the graph have actual coordinates. On the exercise they have variables and there is no way to tell if they are collinear or not.