Describe the shape of the intersection of the plane z= -3 and the plane y=z in three-space.

Well, z= -3 would be a horizontal plane 3 units down the z-axis.

Y=z is an infinite line with x being any value in the y-z plane.

I'm not sure at what line they intersect. I know z must be -3.

Would y be any value, since both z=-3 and y=z extend indefinitely along the y-axis? And would x have to be 0?

Any feedback would be appreciated.