Creation of this resource was inspired by a [url=http://gogeometry.com/problem/p123_area_triangle_similarity.htm]problem[/url] posted by [url=https://twitter.com/gogeometry]Antonio Gutierrez[/url]. [br][br]The [b]LARGE VERTICES[/b] of the [b][color=#bf9000]triangle[/color][/b] below can be moved anywhere at any time. [br]The [b][color=#6aa84f]light green slider[/color][/b] controls the measure of the interior angle with [b][color=#6aa84f]green vertex[/color][/b]. [br][br][b]Questions to consider:[/b][br][br]1) How would you describe the phenomenon you see here in your own words? [br][br]2) How can we formally prove this phenomenon holds true for [b]ANY TRIANGLE[/b]?