Pyramid
tetrahedron, a triangular pyramid
tetrahedron
A di-tetrahedron.
A pyramid.
A triangular dipyramid.A triangular dipyramid.A triangular dipyramid.A triangular dipyramid.
rectangular pyramid
A three-dimensional shape with eight triangular faces is called an octahedron.
A rectangular-based pyramid.
A Pyramid
A triangle itself is a two-dimensional shape, defined by three sides and three angles. However, if we consider a three-dimensional shape that incorporates triangular elements, it could be a tetrahedron, which has four triangular faces. Another example is a triangular prism, which has two triangular bases and three rectangular sides. These shapes extend the properties of triangles into three-dimensional space.
It is a three dimensional shape bounded by polygonal faces (a polyhedron) which has a uniform triangular cross section, parallel triangular bases, and the remaining faces are rectangular.
A triangular prism.