Named for Plato, who theorized that the classical elements were made of these regular polyhedrons, three of the Platonic solids are composed of equilateral triangles: the tetrahedron, octahedron, and ...
The sides of right-angled triangles are labelled opposite, hypotenuse and adjacent. Trigonometry explores the relationship between sides and angles in right-angled triangles. The hypotenuse is the ...