Mathematicians’ Favorite Shapes Hold the Key to Big Mathematical Mysteries ...

Some shapes are made from only straight sides ... A vertex is where two lines meet or join. There are different kinds of triangles. These triangles have sides that are all the same length.

Ever since we published our very first issue 123 years ago—yes, we’re old—Popular Mechanics has endeavored to help you understand all kinds of technological marvels, from the tools in your ...