4
a square based pyramid.
The tetrahedron has 4 equilateral triangles as its faces.
don't no
Tetrahedron or triangular pyramid.
A tetrahedron
The shape you are describing is a triangular pyramid. A triangular pyramid has a base that is a triangle and three triangular faces that meet at a single point called the apex. The base of the pyramid is a rectangle, which is a quadrilateral with four right angles. The triangular faces of the pyramid connect the vertices of the base to the apex.
sphere
The geometric shape that has 1 square face and 4 triangular faces is a pyramid. A pyramid also has five vertices and eight edges. The square acts as the base for the shape on which it sits.
There is no 3-d shape with 4 and 1 = 5 triangular faces.
A square based pyramid.
Square pyramid.