2.4GeoH Day 2 Segment and Angle Proofs.notebook
September 15, 2015
What can we use for reasons in proofs?
2.4 Day 2 Segment and Angle Proofs
I CAN...
Definitions:
complementary, supplementary, linear pair, vertical angles, bisector, congruent, midpoint
Theorems/Postulates:
AIA congruent, AEA congruent, CA congruent, CIA = 180, angle addition, segment addition
Identify and apply algebraic properties
Properties:
Complete segment and angle proofs
addition, subtraction, multiplication, division, reflexive, symmetric, transitive, substitution, distributive
Jul 11­10:27 AM
Jul 15­11:24 AM
Statements
Given: 1 and 3 are complementary
2 and 3 are complementary
Reasons
1. 2. Prove: 1 2
3. m 1+m 3=90
2
4. m 2+m 3=90
3
1
5. m 1+m 3=m 2+m 3
6. m 3=m 3
7. m 1=m 2
8. Jul 15­11:24 AM
Given: C is the midpoint of AE
Jul 15­11:24 AM
B
A
Statements
Reasons
1. C is the midpoint of AE
C is the midpoint of BD
2. C is the midpoint of BD
C
AE BD
3. AE BD
4. AC=CE
Prove: AC CD
5. BC=CD
D
E
6. AE=BD
7. AC+CE=AE
8. DC+CB=DB
9. AC+CE=BC+CD
10. AC+AC=CD+CD
11. 2AC=2CD
12. AC=CD
13. AC CD
Jul 15­11:24 AM
Jul 15­11:24 AM
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