Creation of this applet was inspired by 2 tweets ([url=https://twitter.com/gogeometry/status/851449058334003202]1st tweet[/url] & [url=https://twitter.com/gogeometry/status/852595301730930690]2nd tweet[/url]) from [url=https://twitter.com/gogeometry]Antonio Gutierrez[/url]. [br][br][b][color=#0000ff]How can you formally prove the phenomena this applet informally illustrates? [/color][/b]