# Equilateral-triangles Sentence Examples

If the faces be all equal

**equilateral triangles**the solid is termed the "regular" tetrahedron.If three

**equilateral triangles**be placed at a common vertex with their covertical sides coincident in pairs, it is seen that the base is an equal equilateral triangle; hence four equal**equilateral triangles**enclose a space.In a similar manner, four covertical

**equilateral triangles**stand on a square base.Five

**equilateral triangles**covertically placed would stand on a pentagonal base, and it was found that, by forming several sets of such pyramids, a solid could be obtained which had zo triangular faces, which met in pairs to form 30 edges, and in fives to form 12 vertices.Advertisement