The tetrahedron has 4 equilateral triangles as its faces.
1 square and 4 triangles.
One square, 4 triangles.
A triangle based pyramid.
A tetrahedron; a shape made of four triangles.
Two. 4 faces are triangles and the base is a square.
A truncated tetrahedron.
You are a triangular based pyramid (tetahedron) with 4 faces, 6 edges and 4 vertices.
A triangular prism