Putting them both on the same plot

> p1:=plot3d([x,x^2,z],x=-1.5..1.5,z=-0.5..2.5):

> p2:=implicitplot3d(x^2+4*y^2+4*z^2=16,x=-4..4,y=-2..2,z=0..2):

> display({p1,p2},axes=frame,labels=['x','y','z'],orientation=[60,55]);

This gives us a pretty good idea of what the curve of intersection looks like.

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