Assertion: tetrahedron's triangle | /r/HasProperty | equilateral
Facets:
Source sentences:
text: For the same reason no Heronian tetrahedron can have an equilateral triangle as one of its faces.
text: An irregular tetrahedron (3-sided Pyramid (geometry)) with equilateral base and the top vertex above the center has 6 isometries, like an equilateral triangle.
text: A regular tetrahedron is a special case of both the general tetrahedron and the isosceles tetrahedron for which all four triangular faces are not only congruent, but are also equilateral triangles, i.e. triangles for which all three sides are the same length, and all internal angles are sixty degrees (60°).
text: The solid with the lowest number of sides is the tetrahedron (four equilateral triangles); progressing through the hexahedron or cube, the octahedron, the dodecahedron and the icosahedron (20 sides), the sphere can be considered to have an infinite number of sides.
text: A right angle would be 90 degrees; a tetrahedron is composed of four equilateral triangles, which by definition have equal angles of 60 degrees apiece.
text: If all the triangles are equilateral, the symmetry can also be distinguished by colouring the 8 and 12 triangle sets differently.
text: As a tetrahedron is composed of four equilateral triangles, when placed in a sphere, there will be many golden ratios.
text: The triangles that compose the tetrahedron are equilateral, so it is possible to express its height $$h$$ according to its base:
text: From this it can be seen that a triangle with a vertex at the center of the regular hexagon and sharing one side with the hexagon is equilateral, and that the regular hexagon can be partitioned into six equilateral triangles.