Proof Prompt (D)

How it works ?

1. Theorem:
2. If 2 angles are supplements of congruent angles (or the same angle), then those 2 angles are congruent.
3. (Feel free to move the white points anywhere on the screen you’d like.)
4. Write a 2-column (or paragraph) proof that formally proves what this applet informally illustrates. Be sure to draw an appropriate diagram, state what is given, & state what needs to be proven. Then prove it.