I am running a 3D cad program. Z +up, Y +to left, X + into page.

If I want a new plane (A) that is 20 degrees from the YZ about Y, no problem. Simple rotation about Y axis and enter 20 degrees. If I want a new plane (A) that is 35 degrees from the YZ about Z, no problem. Simple rotation about Z axis and enter 35 degrees.

However if I want a new Plane (A) with a line of intersection between Plane (A) and the XY plane that has an angle with the Y axis of 35 degrees and a line of intersection between Plane (A) and the XZ plane with angle of 20 Z, my mind keep telling me its not as simple as a rotation of 20 about Y followed by a rotation of 35 degrees.

I there a simple enough trig equation to adjust on or both rotation to achieve a set angle about Y and a set angle about Z axis?

I have other ways of generating this plane within cad and drawing a lot of lines. I was just curious if I could bypass all that and just do two successive rotations.