A pyramid
A square is a rectangle with 4 equal sides and 4 equal angles. A rhombus is a parallelogram with 4 equal sides.
Rectangle.
Square
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 pyramid
The figure is a pyramid and the base is a square.
A tetrahedron.
A figure with 4 equal sides and 4 equal angles is a square :)
A square is a rectangle with 4 equal sides and 4 equal angles. A rhombus is a parallelogram with 4 equal sides.
Not necessarily. The solid could be a square based cuboid (hexahedron).
a square
a cube
A triangular based pyramid would seem to fit the given description which has 4 equal sided triangular faces, 6 edges and 4 vertices.
Rectangle.
Square
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"