1. 5-1 Properties of Parallelograms Ch. 5 Test: Fri Dec. 2

2. Parallelogram A quadrilateral where both pairs of opposite sides are parallel.

3. Remember your properties for parallel lines x and y are SSI angles Therefore, x and y are supplements x + y = 180 x and z are also SSI therefore also supplements x + z = 180 So, y = z – Supps of the same angle are congruent. y xz

4. Theorem Opposite angles of a parallelogram are congruent. (x and Y are “opposite angles”) Opposite sides of a parallelogram are congruent. Diagonals of a parallelogram bisect each other. y x

5. Example Given: BC = 8, AB = 15, EC = 8, DB = 18. Find: AD DC AE AC BE DE A D B C E 8 15 8 18 8 15 8 16 9 9

6. Example Given: Angle ADC = 82, Angle EDC = 26 Find angles: ADE ABC EBC BCD BEC A D B C E 82 26 56 82 56 98 56 82 56 98 8 8 9 56

7. TOO—on whiteboards If ABCD is a parallelogram, what is the length of segment BD? A) 10 B) 11 C) 12 D) 5 B C D A E 7 6 5

8. TOO—on WBs Solve for x, y and z 12 x 130 y 10 z

9. Homework Pg. 169-170 #1-12, 16 (4 steps), 19-23 Flashcards – Definition of Parallelogram – 3 Theorems