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Notes – Lesson 4.2-4.3
(Day 2)
Geometry
Name ________________________________________
Proofs
I. What do I need to look for?
A. Given Statements
1. Given: parallel lines: line KJ || GH, KG || JH
alternate interior angles _________________________
same-side interior angles _____________________________
corresponding angles __________________________
2. Given. something bisects something.
BD bisects
 ABC _____________________
BD bisects AC _____________________
3. D is the midpoint of AC _____________________
4. AD is perpendicular to AC ________________________
B. Given information in the picture.
1. vertical angles ____________________
2. reflexive side _____________________
3. write down all tick marks
II.
To prove triangles congruent, I must get:
A. three sides congruent _______________
B. two sides and the included angle congruent _______________
C. two angles and the included side congruent ________________
D. two angles and a side congruent _______________
III. Proofs.
Given: AB = CB, AD = CD
Prove: ABD  CBD
Use this picture for
2, 3, and 4.
Given: AE = XE
<B = <Y
Prove:  ABE =  XYE
Given: AD bisects  BAC
AB = AC
Prove:  ABD =  ACD
Given: AB = DC
 BAC =  DCA
Prove:  ABC =  CDA
Given:
K = M
KL = ML
Prove:  JKL =  PML
Given: DB bisects AC
AD || BE
AD = BE
Prove:  ADB =  BEC
1. DB bisects AC
1. ___________________
2. AD || BE
2. ____________________
3. AD = BE
3. __________________
4. AB = BC
4. ______________________
5.
1 = 2
6.  ADB =  BEC
Given:
B = E
BA = ED
BA  AC
ED  FD
Prove:  ABC =  DEF
Given: KJ || GH
1 = 2
Prove:  GHK =  JKH
5. _______________________
6. ________________________