▪ Geometry Problems and Puzzles

 List of problems and puzzles 

▪ The asymmetric_propeller

A theorem popularized by Martin Gardner in an article in The College Journal of Mathematics.

▪ Common tangents of two circles

A relationship between the common tangents of two circles.

▪ Equal chords in two circles

An application of the “power of a point” theorem.

▪ The maximal angle problem

On how to get the widest angle of view.

▪ The rings of Saturn

Where to stand to get the best view of the rings?

▪ An inequality concerning equilateral triangles

…and a nice solution by Dan Hoey.

▪ Another problem concerning equilateral triangles

Intriguing puzzle proposed by Steve Gray.

▪ An equilateral triangle inscribed in a rectangle

Maybe easy to solve… I don't know.

▪ A triangle's incenter via algebra

… and extension to tetrahedra.