Exactly how many triangles can you count in this fun triangle puzzle?

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 triangle shape on sweatshirts and jumpers has become more of a fashion trend in recent years - but it turns out there's a practical reason for the design dating back a century ...

Design Squad is available to stream on pbs.org and the free PBS App, available on iPhone, Apple TV, Android TV, Android smartphones, Amazon Fire TV, Amazon Fire Tablet, Roku, Samsung Smart TV, and ...

The base and the perpendicular height are at right angles to each other. The measurements used must be in the same units. For example, to work in cm a 45 mm measurement would have to be converted to ...