octagonal pyramid :)
A pyramid
Tetrahedron has three sides and a base all triangular.
It depends on what type of shape you are trying to find the area. If it is a rectangle, you do base times height. For triangles, you do base times height divided by two. For a circle, it is Pi*R^2.
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.
There is a contradiction in your question. If the base has four equal sides then is it a square so not all the faces are Triangles. However if the base is a square and the rest of the faces are triangles then your object is a "Square-based Pyramid"
A triangular prism.
A pyramid.
pyramid
A pyramid.
The figure is a pyramid and the base is a square.
A pyramid.
It is a triangular prism
One square or rectangle as it's base, and the other sides are triangles.
The answer is a pyramid.
triangular pyramid
A pyramid.