Well, any shape with a triangular face. I assume that you mean a shape that only has (identical) triangles for faces. There are 2: the tetrahedron with 4 triangles, and the icosahedron with 20 triangles. * * * * * What about a triangular dipyramid? Two triangular pyramids stuck together along one face?
The tetrahedron has 4 equilateral triangles as its faces.
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A pyramid - it has a square base, and four triangles meeting to a point at the top.
square-based pyramid
sqare based pyramid
Well, any shape with a triangular face. I assume that you mean a shape that only has (identical) triangles for faces. There are 2: the tetrahedron with 4 triangles, and the icosahedron with 20 triangles. * * * * * What about a triangular dipyramid? Two triangular pyramids stuck together along one face?
rectangular pyramid
The tetrahedron has 4 equilateral triangles as its faces.
a pentagonal pyramid
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A triangular prisim (3 faces on sides, one face on bottom).
A pyramid - it has a square base, and four triangles meeting to a point at the top.
square-based pyramid
4 faces are triangles and 1 face is a square the square face is the base of the pyramid
A rectangular-based pyramid.
The tetrahedron. If one of the four triangles is equilateral and all others are isosceles, then one might also call it a (triangular-based) pyramid.