Where Do Two Lines Intersect in 3 Dimensions?

I’m a physicist, not a mathematician. So, when we talk about straight lines in 3 dimensions I find it easier to use real examples. Don’t worry, I am going to get to those parametric and symmetric forms of 3D lines that you see in maths, but let’s start with a particle moving with a constant velocity.

Parametric Form, Symmetric Form, and Velocity Form of a 3D