Okay, this might be easy for some, but for me right now, I am not able to do this change of variable easily. What I want to calculate is the volume of a cylinder intersected by a plane as shown in this youtube video:

With the equation of the plane:

2x + z = 4

And the equation for the cylinder:

x^2 + y^2 = 9

Could you teach me/guide me on how do I decompose this triple integral into a final 1d integral?