GoGeometry Action 165!

Creation of this resource was inspired by a [url=https://twitter.com/gogeometry/status/1017948642597064704]tweet[/url] from [url=https://twitter.com/gogeometry]Antonio Gutierrez[/url] (GoGeometry). [br][br]You can move any LARGE POINT (the [b]2 white points[/b] and [color=#ff7700][b]soon-to-appear ORANGE POINT[/b][/color]) anywhere you'd like at any time. [br][br][b]Questions to consider:[/b] [br][br][b][color=#ff00ff]What is the measure of the pink angle? [br][br]How can we formally prove the phenomenon dynamically illustrated here? [/color][/b]
Quick (Silent) Demo

Information: GoGeometry Action 165!