1. Properties of Parallelograms
Ch 6-2

2. Parallelogram or //ogram or
Definition: A quadrilateral with opposite sides parallel.

3. 1 2 4 3 5 6 8 7
2   Corr  Thm
4  7 Alt. Int.  Thm
2   Trans. Prop. 
6   Corr  Thm
8  3 Alt. Int.  Thm
6   Trans. Prop. 

4. //ograms  Opposite s are 

5. 1 5 6 2 3 7 4 8
1 and 2 are Supp. Linear Pair Thm
1   Corr.  Thm
2 and 3 are Supp. Substitution
or Consec. Int.  Thm

6. //ograms  Consecutive angles are supplementary.Q T S R
mQ + mR = 180o
mR + mS = 180o
mS + mT = 180o
mT + mQ = 180o

7. If a parallelogram has one right angle, then it has four right angles.
Not on vocab sheet!
If a parallelogram has one right angle, then it has four right angles.

8. Corr. Parts of  figures are B 1 3 4 2 C D
1   Opposite  are 
3   Alt. Int.  Thm
Reflexive Prop. 
ABC  DCB AAS   Thm
Corr. Parts of  figures are 

9. Parallelograms  Opposite sides are 

10. Corr. Parts of  figures are B D C E
ABE  DCE Alt. Int.  Thm
BAE  CDE Alt. Int.  Thm
AB  CD Opposite sides 
ABE  DCE ASA   Thm
AE  DE CE  BE
Corr. Parts of  figures are 
E is the midpoint of AD and CB
Def of Midpt.

11. //ograms  Diagonals bisect each other.

12. ACD  CAB Diagonals of a parallelogram separates the
parallelogram into two congruent triangles.
ACD  CAB A B C D

13. ABCD is a parallelogram. Find x. 4 58 20 A B C D

14. ABCD is a parallelogram. Find mBCD.54 64 62 58

15. ABCD is a parallelogram. Find mBDC.54 64 62 58 A B C D

16. Homework
Chapter 6-2
Pg 328:
# 3-11, 13proof,
15-30, 46-49