SAS
The SAS Triangle Congruence Theorem states that 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 prove this theorem.
Play with the applet then answer the questions that follow.
As you do, feel free to move the BIG WHITE POINTS anywhere you'd like on the screen!
Questions:
1) What geometry transformations did you observe in the applet above? List them.
2) What common trait do all these transformations have?
3) Go to this link and complete the first 5 exercises in this GeoGebra Book chapter.