Random 3D Solid (AR Modeling Challenge)

Topic:
Functions
Using only 2 surface equations (with domain restrictions), how can we construct the 3D surface seen in the screencast below? Try to construct this surface using GeoGebra Augmented Reality or in GeoGebra's 3D Graphing Calculator. Note: The blue surface has vertices (5,0,0), (-5, -5, 0), (-5, 5, 0), (0, 5, 5), & (0, -5, 5). The pink plane has vertices at (5, 0, 0), (-5, -5, 0), & (0, -5, 5).