Trisect the angles of any triangle and the adjacent intersections will form an equilateral triangle. Drag the corners and see for yourself!

Written using the D3 visualisation library. Inspired by A Better Nature.

Requires a SVG-capable browser e.g. Mozilla Firefox, WebKit (Google Chrome, Safari &c.) or Internet Explorer 9.

- A. Bogomolny, Morley's Miracle from Interactive Mathematics Miscellany and Puzzles. Includes a long list of different proofs, in particular John Conway's proof is rather elegant.
- Morley's Trisection Theorem: a detailed proof at MathWorld.
- Morley's Theorem at MathWorld.
- Morley's trisector theorem at Wikipedia.

© Jason Davies 2012.