1. Factoring Warm-Up

2. Discuss Quizzes

3. 9.4 Glide Reflections and Compositions
Objectives:
Make composition transformations
Identify types of composition transformations

4. Vocabulary composition – when two or more transformations are combined
glide reflection – a transformation of translation and a reflection

5. Use the information below to sketch the image CD after a composition.
C(2, 0) and D(3, 3)
1. Reflection over in the x-axis
2. Rotation 90°
counterclockwise about
the origin
Is the composition a glide reflection?

6. Use the information below to sketch the image CD after a composition.
C(2, 0) and D(3, 3)
1. Rotation 90° CCW about
the origin
2. Reflection over the x-axis
Will the composition be the same?
Is the composition a glide reflection?

7. Use the information below to sketch the image DQRS after a composition.
Q(2, -3), R(4, -4) and S(5, -1)
1. Translation: (x, y) ® (x, y + 5)
2. Reflection over the y-axis
Is the composition a glide reflection?

8. Use the information below to sketch the image EF after a composition.
E(-3, 5) and F(2, 7)
1. Rotation 180° ccw about the origin
2. Translation:
(x, y) ® (x – 3, y + 1)
Is the composition a glide reflection?

9. Describe the composition.A
B’’
C’’ B C
A’’ C’ B’ A’
1. Rotate 180° clockwise about (1, 1)
2. Translate (x, y)  (x – 2, y + 4).

10. Describe the composition.y x
1. Reflect about the y-axis
2. Translate (x, y)  (x, y + 2).

11. What transformations are needed to solve the puzzle?

12. What transformations are needed to solve the puzzle?

13. What transformations are needed to solve the puzzle?

14. What transformations are needed to solve the puzzle?

15. What transformations are needed to solve the puzzle?

16. Who knows this game?
What makes Tetris so cool? It uses Geometry!

17. Let’s Play Tetris!
Class challenge!

18. Exit Ticket
On the bottom of the notebook paper you used for the Tetris activity, answer the following:
1. For which Tetris pieces would a rotation not be useful? Why?
2. For which Tetris pieces would a reflection not be useful? Why?
3. Determine the composition of transformations that maps ABC to DEF:

19. Geometry
Homework:
p.656 #27, 35, 41, 43, 45, 46

20. ΔJKL has vertices J(2, 3), K(5, 2), and L(3, 0)
ΔJKL has vertices J(2, 3), K(5, 2), and L(3, 0). Graph ΔTUV and its image after a translation along 3, 1 and a rotation 180° about the origin. What are the new coordinates of L''?
A. (–3, –1)
B. (–6, –1)
C. (1, 6)
D. (–1, –6)
Example 2