The three angles in a triangle add up to \(180^\circ\). If two of the angles are known then the third can be calculated by following these steps: Add the two known angles together. Subtract the total ...

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 ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. They all have straight rays or sides if they're part of a shape and a vertex, that's the point where ...