Proof Prompt (D)
Theorem:
If 2 angles are supplements of congruent angles (or the same angle), then those 2 angles are congruent.
(Feel free to move the white points anywhere on the screen you'd like.)
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.
