As a class, we have just formally proven the [b]Triangle-Angle-Sum-Theorem[/b]. (An informal illustration of this theorem can be seen [url=https://www.geogebra.org/m/FAhtKpR5]here[/url].) [br][br]Because we know what we now know, we should be able to make some other conclusions that are an immediate consequence of this theorem. Such a conclusion is referred to as a [b][color=#9900ff]corollary[/color][/b]. A [color=#9900ff][b]corollary is a statement (another theorem, really) that can automatically be proven true as a result of a "bigger-picture-theorem"[/b][/color]. [br][br]One [color=#9900ff][b]corollary[/b][/color] that is easy to prove as a result of the [b]Triangle-Angle-Sum-Theorem[/b] will be illustrated below (once you slide the slider). [br][br]Interact with this applet for a few minutes, then answer the questions that follow. As you do, feel free to move the white points anywhere you'd like.