1. GT Geometry Drill
Pick up a paper and complete
Classroom Ex #1- 10
# 2 then
#8 then 2z = 2
EFAB

2. • #1.Write a two column proof
• Given: AB=CD
• Prove: AC=BD
A B C D

3. Proof
Statement
1. AB=CD
2. BC=BC
3. AB +BC = CD + BC
4. AB +BC = AC
CD + BC = BD
5. AC = BD
Reason
1. Given
2. Reflexive property of
Equality
3. Addition Property of
Equality
4. Segment Addition
Postulate
5. Substitution Property
of Equality

5. Proofs
• Example 1
• Given:
• Prove:
D
BODmAOCm
31 mm
CB
A
O
3
21