# SAS: Dynamic Proof!

- Author:
- Tim Brzezinski

- Topic:
- Congruence, Triangles

The

**states that**__SAS Triangle Congruence Theorem__**if 2 sides and their included angle of one triangle are congruent to 2 sides and their included angle of another triangle, then those triangles are congruent.**The applet below uses transformational geometry to dynamically prove this very theorem. Interact with this applet below for a few minutes, then answer the questions that follow. As you do, feel free to move the**BIG WHITE POINTS**anywhere you'd like on the screen!## Q1:

What geometry transformations did you observe in the applet above? List them.

## Q2:

What common trait do all these transformations (you listed in your response to (1)) have?

## Q3:

Go to this link and complete the first 5 exercises in this GeoGebra Book chapter.