CCGPS AG 1.8.1 Example 4

Prove that vertical angles are congruent given a pair of intersecting lines, and .
  1. Draw a diagram and label three adjacent angles.
  2. Start with the Supplement Theorem.
  3. Use substitution.
  4. Use the Reflexive Property.
  5. Use the Subtraction Property.
  6. Use the definition of congruence.
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