1. 9.3 – Perform Reflections

2. Reflection:
Transformation that uses a line like a mirror to reflect an image
Line of Reflection:
Mirror line in a reflection

3. A reflection in a line m maps every point P in the plane to a point , such that:
If P is not on m, then m is the perpendicular bisector of
If P is on m, then

4. Reflect point P(5, 7) in the given line.
x – axis
P(5, 7) becomes P
A reflection in the x-axis changes
(x, y) into _______
(x, –y)

5. Reflect point P(5, 7) in the given line.
y – axis
P(5, 7) becomes P
A reflection in the y-axis changes
(x, y) into _______
(–x, y)

6. Reflect point P(5, 7) in the given line.
y = x
P(5, 7) becomes P
A reflection in the y = x changes
(x, y) into _______
(y, x)

7. Graph the reflection of the polygon in the given line.
x – axis

8. Graph the reflection of the polygon in the given line.
y – axis

9. y = x (–1 , –3) (–3, –1) (2, –4 ) (–4, 2) (3, 0) (0, 3)
Graph the reflection of the polygon in the given line.
y = x
(–1 , –3)
(–3, –1)
(2, –4 )
(–4, 2)
(3, 0)
(0, 3)

10. Graph the reflection of the polygon in the given line.
x – axis

11. Graph the reflection of the polygon in the given line.
x = –1

12. Graph the reflection of the polygon in the given line.

13. 9.4 – Perform Rotations

14. Rotation:
Transformation that turns a figure about a fixed point
Center of Rotation:
The point that the rotation happens around
Angle of Rotation:
Degree the figure is rotated counterclockwise

15. A rotation about a point P through an angle of x° maps every point Q in the plane to a point such that:
If Q is not the center of rotation, then
and x° Q P

16. A rotation about a point P through an angle of x° maps every point Q in the plane to a point such that:
If Q is the center of rotation, then Q

17. 1. Match the diagram with the angle of rotation.
B. 90°

18. 1. Match the diagram with the angle of rotation.

19. 1. Match the diagram with the angle of rotation.

20. Counter-clockwise degree of rotation: _______ 180°
State if the rotation is 90°, 180°, or 270° counter-clockwise.
Counter-clockwise degree of rotation: _______
180°

21. Counter-clockwise degree of rotation: _______ 90°
State if the rotation is 90°, 180°, or 270° counter-clockwise.
Counter-clockwise degree of rotation: _______
90°

22. Counter-clockwise degree of rotation: _______ 270°
State if the rotation is 90°, 180°, or 270° counter-clockwise.
Counter-clockwise degree of rotation: _______
270°

23. 6. Find the value of each variable in the rotation.
x = 4
z = 3
y =
z + 2
y =
3 + 2
y = 5

24. 6. Find the value of each variable in the rotation.
4s = 24
s = 6
r =
2s – 3
r =
2(6) – 3
r = 12 – 3
r = 9

25. HW Problems
9.3
9.4 WS
3-7, 9, 12 (Graph on worksheet)
3-8, 20, 21, 44-46
ROTATION WS
9.3 #7