1. Section 2.5: Proving Statements about Segments

2. Definitions
Theorem:
A true statement that follows as a result of other true statements.
We can prove theorems using two-column proofs, which show numbered statements/steps along with their reasons that show the logical order of an argument.

3. Theorem 2.1 – Properties of Segment Congruence
Reflexive
For any segment AB, AB ≅ AB
Symmetric
If AB ≅ CD, then CD ≅ AB
Transitive
If AB ≅ CD, and CD ≅ EF, then AB ≅ EF
REMEMBER: Put in the Definitions/Properties/ Postulates/Theorems/Formulas portion of your notebook