Question

How do I find the slope of a line through two points in three dimensions?

Answer 1

Since we are talking about a line in 3-D, it is more appropriate to talk about its direction vector than its slope. To find the direction vector `vec{v}` of the line passing through two points `(x_1,y_1z_1)` and `(x_2,y_2,z_2)` can be found by

`vec{v}=(x_2-x_1,y_2-y_1,z_2-z_1)`.