The three-dimensional shape consisting of 4 triangles is called a pyramid, or a triangular prism.
Square pyramid
A tetrahedron (triangular pyramid).
pyramid
duodecahedron is a 3D shape that has 20 triangles as it's base
A rectangular based pyramid would fit the given description
Tetrahedron or Triangular Pyramid
Square pyramid
The simplest such shape is PYRAMID.
There can be no closed 3D shape with only one square and 3 triangles.
A tetrahedron (triangular pyramid).
square based pyramid
There is no 3D shape with 6 faces: 4 rectangles and 2 triangles. See the link for all forms of hexahedra.
A TETRAHEDRON. Incorrectly named as a 'triangular pyramid'.
Is a PYRAMID NB Do NOT confuse with a TETRAHEDRON, which is three triangles on a triangular base. Thereby making a shape of FOUR sides.
A three-sided pyramid, also termed a triangular prism.
A 3D shape with all triangular faces can be a tetrahedron pyramid.
pyramid