# Cut a cube into 5 objects

Cut a cube into 5 3D objects with 6 edges each.

Hint:

(I assume there is only one solution): only 4 of the objects are pyramids, ie tetrahedrons with one vertex containing only right angles

• Are you sure there is no error in your question? 4 with 4 edges and 4 as pyramids out of 5 objects implies at least 3 pyramids with 4 edges. Under the usual definitions of which I'm aware there's no such thing. Should this have an enigmatic tag or something? Aug 28, 2019 at 3:50
• Did you mean faces maybe? Aug 28, 2019 at 4:30
• @Dr Xorile Yes, as it is presented I have a drawing of this. I may tell you that this is a result (hint?) of unfolding of a certain 4D right angle pyramid and rearranging the components of its "surface" (volume!)
– Moti
Aug 28, 2019 at 4:36
• @athin I meant 5 3D objects.
– Moti
Aug 28, 2019 at 4:36
• @Dr it is clear that you have 4 pyramids - 4 edges implies a pyramid. The additional infor mation of 4 pyramid shows that the 5th object is not a pyramid.
– Moti
Aug 28, 2019 at 4:40

Draw a diagonal line on one of the faces and the orthogonal line on the opposite face. Join the ends of those lines together. With those as the cut points you get four corners of the cube (each with 4 sides) and the remainder is a tetrahedron with 6 edges.

The above is now correct given the update made by the OP.

Here's a rendering of the dissection done in TinkerCad: