NO!!!
A triangle is a 2-dimensional shape of three sides; archaically a 'trigon'.
A polyhedron is a 3-dimensional solid of many sides.
Octogon
A regular OCTAHEDRON.
Yes it is a tetrahedron
Tetrahedron - a pyramid with a triangular base.
7 faces
The answer is a polyhedron
it is a triangle prism
square and hexagon
Tetrahedron
Yes
pyramid
Tetrahedron
There are many possible answers.
yes it is called a octahedron
It is a tetrahedron = a triangle based pyramid.
A tetrahedron, a triangle based pyramid, an octahedron, an icosahedron plus many more.
if you mean common: one of the triangle, square, and pentagon vertion of pyramid, dipyramid, and gyrolongated dipyramid. a total of 9.