Rational Trigonometry/A

Available as a playlist https://www.youtube.com/playlist?list=PL3C58498718451C47


 * Rational Trigonometry/0 - An invitation to Geometry
 * 1) Rational Trigonometry/1 - Intro to Rational Trigonometry
 * 2) Rational Trigonometry/2 - Quadrance via Pythagoras and Archimedes