# GoGeometry Action 121!

- Author:
- Tim Brzezinski

Creation of this applet was inspired by a tweet from Antonio Gutierrez.
You can move the

**LARGE VERTICES**of the**RIGHT TRIANGLE**anywhere you'd like at any time.**What is the measure of the pink angle?**What is the measure of the angle with**green vertex**that has sides that pass through the**other 2 green points**?**How can we formally prove this to be true?**