1. How can you tell if an object is reflected?
Reflection
1. Pick up Homework from table. 2. Copy down the Essential Question (EQ). 3. Work on the Warm-up.
Essential Question
How can you tell if an object is reflected?
Warm Up: Answer the question.
Describe the transformation from blue to red.

2. Identifying a Reflection
Is it a reflection? Explain
Its is a reflection because, the red figure is flipped to make the blue figure
Its is a not a reflection, because, the red figure is does not flipped to make the blue figure

3. Tell whether the blue figure is a reflection. Explain

4. Reflect over the __ –axis

5. Reflect over the __ – axis?

6. Fill in the points for A

7. Fill in the points for A’

8. What do you notice? What changed?
Pre Image → Image ( 1, 4 ) → ( 1, -4 ) ( 1, 1 ) → ( 1, -1 ) ( 4, 1 ) → ( 4, -1 ) The y sign changed. RULE: When reflection over The X- axis ( x, y ) → ( x, -y )

9. Fill in the points for A

10. Fill in the points for A’

11. What do you notice? What changed?
Pre Image → Image
( 1, 2 ) → ( -1, 2 )
( 4, 2 ) → ( -4, 2 )
( 1, 5 ) → ( -1, 5 )
( 4, 5 ) → ( -4, 5 )
The x sign changed.
RULE: When reflection over
The Y- axis
( x, y ) → ( -x, y )

12. Reflection on Coordinate Grid Lesson 08-21-18
1. Copy down the Essential Question (EQ). 2. Work on the Warm-up.
Essential Question
How is reflecting over the x-axis
different from reflecting over the y –axis ?
Warm Up: Answer the question.
Name and Describe the transformation from blue to red.

13. Lets revisit yesterdays problem

14. Lets revisit yesterdays problem

15. Graph the image of the figure using the transformation given

16. Graph the image of the figure using the transformation given

17. Graph the image of the figure using the transformation given

18. Graph the image of the figure using the transformation given

19. Find the coordinates of the vertices of each figure after the given transformation.

20. R‘ (3 , -5), N’ ( 4, 0), V’ ( 2, -1) , E(0, -4)
K ‘ ( 1 , 1), N’ ( 4, 0), Q’ ( 4, 4)

21. Write the rule to describe each transformation
Reflect over the y- axis

22. How is rotation different from reflection?
1. Copy down the Essential Question (EQ). 2. Work on the Warm-up.
Essential Question
How is rotation different from reflection?
Warm Up: Answer the question.
Describe what happen in the 3 different pictures

23. The meaning of a Words

24. Center of rotation: the center point where the object turn.
Vocabulary
Rotation: the turn transformation where an object rotates around a point.
Center of rotation: the center point where the object turn.
We will use ( 0, 0 ) as the center of rotation
Angle of rotation: How much the object will turn

25. Animation of Rotation
Center of Rotation
4/24/2019

26. Example 1: Identifying Rotations
Tell whether each transformation appears to be a rotation. Explain. A. B.
No; the figure appears
to be flipped.
Yes; the figure appears
to be turned around a point.

27. Your Turn: Tell whether each transformation appears to be a rotation.
No, the figure appears to be a translation.
Yes, the figure appears to be turned around a point.

28. Degree of Rotation

29. Degree of Rotation
-90 90

30. Rotation on Coordinate Grid 08-23-18
1. Copy down the Essential Question (EQ). 2. Work on the Warm-up.
Essential Question
How do you tell if an object is rotated by looking at its points.
Warm Up: Answer the question.
Describe any patterns in the picture

31. 90 clockwise rotation Formula (x, y)  (y, x) English Formula:
Change the sign for the x, then switch the x and y.
A(-2, 4)
A’(4, 2)
4/24/2019

32. Example: Rotate (-3, -2) 90 clockwise
Formula
(x, y)  (y, x)
English Formula:
Change the sign for the x, then switch the x and y.
A’(-2, 3)
(-3, -2)
4/24/2019

33. 90 counter-clockwise rotation
Formula
(x, y)  (y, x)
English Formula:
Change the sign for the y, then switch the x and y.
A’(2, 4)
A(4, -2)
4/24/2019

34. Example: Rotate (-5, 3) 90 counter-clockwise
Formula
(x, y)  (y, x)
English Formula:
Change the sign for the y, then switch the x and y
(-5, 3)
(-3, -5)
4/24/2019

35. 180 rotation Formula (x, y)  (x, y) English Formula:
Just change the sign for the x and y
A’(4, 2)
A(-4, -2)
4/24/2019

36. Example: Rotate (3, -4) 180 Formula (x, y)  (x, y)
English Formula:
Just change the sign for the x and y
(-3, 4)
(3, -4)
4/24/2019

37. 90 CW (x, y)  (y, x) 90 CCW (x, y)  (y, x)
Rotation Formulas
90 CW (x, y)  (y, x)
90 CCW (x, y)  (y, x)
180 (x, y)  (x, y)
4/24/2019

42. Degree of Rotation
-90 90

43. Rotation on Coordinate Grid Part 2 08-24-18
1. Turn in your homework to the table. 2. Copy down the Essential Question (EQ). 3. Work on the Warm-up.
Essential Question
How is the rotation transformation
similar to the reflection transformation?
Warm Up: Answer the question.
Does the shape get larger during a rotation?

44. Draw the shape and rotate it 3 different ways:
(1) 90°clockwise, (2) 90°counterclockwise, and (3) 180°

45. 90°clockwise
(2) 90°counterclockwise
(3) 180°

46. Draw the shape and rotate it 3 different ways:
(1) 90°clockwise, (2) 90°counterclockwise, and (3) 180°

47. 90°clockwise
(2) 90°counterclockwise
(3) 180°

48. 90°clockwise
(2) 90°counterclockwise
(3) 180°

50. Formula
(x, y)  (y, x)
English Formula:
Change the sign for the y, then switch the x and y.

51. Formula
(x, y)  (y, x)
English Formula:
Change the sign for the x, then switch the x and y.

52. Formula
(x, y)  (x, y)
English Formula:
Just change the sign for the x and y