A triangular prisim (3 faces on sides, one face on bottom).
A three-dimensional figure or shape, such as a tetrahedron, has four faces. These faces are equilateral triangles. A tetrahedron also has four vertices and 6 edges.
A square and rectangle both have congruent triangles in them.
If you have 2 EQUILATERAL triangles, and you stack them on their respective hypotenuses, the result: SQUARE. If you have 2 ISOSCELES triangles, and you stack them on their respective hypotenuses, the result: RECTANGLE. If you have 2 OBTUSE triangles, and you stack them on their respective hypotenuses, the result: PARALLELOGRAM.
This shape is called a Icosahedron , I think.
Regular polygons have congruent angles such as squares and equilateral triangles.
A tetrahedron has four equilateral triangles as sides
A four faced figure is a tetrahedron. If they are all congruent triangles, they are all equilateral triangles and it is a regular tetrahedron - one of the 5 Platonic Solids.
Differences: Squares have 4 sides / equilateral triangles have 3 sides. Squares have 90 degree angles / equilateral triangles have 60 degree angles. Squares have 2 diagonals / equilateral triangles have none Similarities: All sides of the shape are congruent All angles of the shape are congruent
The Platonic solid known as an octahedron would fit the given description
The tetrahedron has 4 equilateral triangles as its faces.
square based pyramid
A hexagon based pyramid.