There is no pentahedron with only one triangular face.
There are 2 triangle base faces, and 3 rectangle faces. 5 total faces.
5 faces
5
5 .
5
5
Yes it has 5 faces, 9 edges and 6 vertices
5
it is a triangular prism
5 or 6
Pyràmid
A triangle has 3 sides and 3 vertices. Strictly speaking, the interior of the triangle is not part of the triangle so it has no faces. However, a triangular lamina will have two faces - one from above and one from below.