Hello, wirefree!

Given the -coordinate of a point on a plane

and the angle the plane makes with the horizontal,

could the equation of the plane be established?

I would say: No.

Visualize a "pup tent".

Code:* / * P / o / * / * / / \ / / \ / / \ \ * / * \ * / * \ * / * \ * / *\ * *

The two sloping sides make the same angle with the horizontal

. . and both sides contain the point