can a plane lie on 3 coordinates x, y and z or not?

may be that a plane can onlylie only on xy or xz or yz?

I don’t figure out this in my mind!

thanks

Did you mean: can a plane contain all three coordinate axis? No. However, it can contain points p0, p1, p2 where p0 = s * (1,0,0), p1 = t * (0,1,0), p2 = r * (0,0,1) for some real numbers s,t, and r including the trivial s = t = r = 0. In other words it can contain points from all three coordinate axis, for example the origin.