This follows exactly the same procedure as above, but now it becomes slightly more tricky
to calculate the values of **y1** and **y2**. You will first have to define your plane.
There are a couple of ways to do this, but I shall show you the method where you define the
plane by a point on the plane and a vector perpendicular to it.
Suppose the normal to the plane is **(Na, Nb, Nc)**

and the point whose distance from the plane you want to determine is **(Px, Py, Pz)**

(**Na*****Px** + **Nb*****Py** + **Nc*****Pz**)
Distance = -----------------------
sqrt(**Na**^{2} + **Nb**^{2} + **Nc**^{2})

This is assuming that the plane passes through the origin.

### Important Notes