Regular polygons have congruent angles such as squares and equilateral triangles.
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.
Triangular Pyramid
The Platonic solid known as an octahedron would fit the given description
The tetrahedron has 4 equilateral triangles as its faces.
An Icosahedron.
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.
Triangular Pyramid
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
An octahedron.
A hexagon based pyramid.