Assertion: tetrahedron's face | /r/HasProperty | triangle
Facets:
Source sentences:
text: One face is a heptagon (usually regular), and the remaining seven faces are triangles (usually isosceles).
text: Regular polygons of six or more sides have only angles of 120° or more, so the common face must be the triangle, square, or pentagon.
text: Therefore, the faces can only be triangles, squares, or pentagons, so 3 ≤ m ≤ 5.
text: It is a pyramid where the base is a triangle—or, even more specifically, all four faces of the shape are triangles.