1. Proving Statements about Segments
Chapter 2 Section 2.5
Proving Statements about Segments

2. Warm-Up

3. Properties of Segment Congruence
Segment congruence is reflexive, symmetric, and transitive
Reflexive:
Symmetric:
Transitive:
Theorem: A true statement that follows as a result of other true statements. Theorems must be proved true

4. Match the statement with the Property of Congruence
Reflexive Property of congruence
Transitive Property of congruence
Symmetric Property of congruence

5. Mark the diagram with the given information

6. Mark the diagram with the given information

7. 1. Given
2. Given
3. Substitution
4. Definition  Segments
5. Given
6. Transitive

8. 1. Given
2. Reflexive
3. Addition
4. Segment Addition
5. Segment Addition
6. Substitution

9. Paragraph Proof: When a proof is written in paragraph form.
Since AL = SK and by reflexive property LS = LS, from the addition property of equality it follows that AL + LS = SK + LS. Also by segment addition postulate we can say that AL + LS = AS and SK + LS = LK. Thus a simple substitution allows us to arrive at AS = LK
You may use any proof style (two-column or paragraph) at anytime on any assignment.