1. Unit 9 Lesson 6.2A: Parallelograms
CCSS
Lesson Goals
G-CO 11: Prove theorems about parallelograms.
State the definition and properties of a parallelogram
Use the properties of a parallelogram to solve for missing lengths and angle measures.
ESLRs: Becoming Effective Communicators, Competent Learners
and Complex Thinkers

2. Parallelograms A quadrilateral with
both pairs of opposite sides parallel.
both pairs of opposite sides congruent.
both pairs of opposite angles congruent.
supplementary consecutive angles.
diagonals that bisect each other.
This is the definition

3. Parallelograms A quadrilateral with
definition
A quadrilateral with
both pairs of opposite sides parallel. A B D C

4. Parallelograms A quadrilateral with
property
A quadrilateral with
both pairs of opposite sides congruent. A B D C

5. Parallelograms A quadrilateral with
property
A quadrilateral with
both pairs of opposite angles congruent. A B D C

6. Parallelograms A quadrilateral with diagonals that bisect each other.
property
A quadrilateral with
diagonals that bisect each other. A B C D E

7. Parallelograms A quadrilateral with supplementary consecutive angles.
property
A quadrilateral with
supplementary consecutive angles. A B D C

8. Example

9. You Try

10. You Try

11. You Try

12. You Try

13. You Try

14. You Try

15. You Try

16. You Try

17. Example
Find JH and LH K J 6 6 8 8 L G H

18. Example
Find the other angle measures K J
105o
105o G H

19. Example
Find the other angle measures K J
75o
105o
105o G H

20. Example
Find the other angle measures K J
75o
105o
105o
75o G H

21. You Try K J G H

22. Example
Find the value of each variable in the parallelogram

23. Example
Find the value of each variable in the parallelogram

24. Example
Find the value of each variable in the parallelogram

25. Summary
Create a mnemonic or acronym to remember the characteristics of a parallelogram.

26. Today’s Assignment
p. 333: 1 – 11, 20 – 25, 27 – 39 o