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 ...

Use a ruler, protractor and a pair of compasses to construct a triangle accurately. After the triangle has been constructed, leave the construction lines visible so each stage of the process is shown ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to ...