Is a plane that is parallel to any one of these 3 coordinate planes also considered a coordinate plane, such as x=4 or z = -3?

1 Answer
Dec 19, 2017

Let's examine x = 4

In terms of a point (x,y,z)

x + 0y + 0z = 4

The normal vector to this scalar equation to of a plane is:

hati + 0hatj+0hatk

A vector form of this plane is:

(x,y,z) = (4,0,0) + s(0hati+hatj+0hatk) + t(0hati+0hatj+hatk)

The 3 parametric equations for this plane are:

x = 4, y = s, z=t

It is certainly a plane.

We can do the same thing with z=-3

Please think of it this way:

If x=0, is the y-z plane, y=0 is the x-z plane, and z = 0 is the x-y plane, then x = k_1 is a y-z plane with an x coordinate that is k_1, y= k_2 is an x-z plane with an y coordinate that is k_2, and z=k_3 is an x-y plane with a z coordinate that is k_3.