A triangular prism has 5 flat faces.
A triangular prism.
A pyramid * * * * * Or it could be a triangular prism.
Triangular prism (toblerone shape)
All the faces of a triangular prism must be flat. So finding them should not be too difficult!
There are two 3D shapes with five faces: Triangular prisms and rectangular pyramids.
A triangular prism has two triangular faces and three rectangular ones.
There are five of them.
If you mean a tetrahedron then it is a triangular based pyramid with 4 flat faces
It has 5 SIDES