Aim #73: How do we rotate figures
counterclockwise?
(Unit 7 - Transformations)
2-27-17
HW #73: Positive Rotations Handout
Do Now:
Graph and label ΔA'B'C', the reflection of ΔABC across the given line.
1.
y-axis
3. x = 1
2. x-axis
B
C
4. y = -2
C
A
A
A
A
B
C
C
B
B
5. What are the coordinates of the image of the point (9, -1) after a translation
4 units up and 10 units left? In which quadrant will the image lie?
Rotations
Rotation: transformation where the figure is turned
about a fixed point (represented by a capital "R")
We will rotate figures about the origin in the
coordinate plane.
There are 2 types of rotational directions:
1) counterclockwise - positive rotation
2) clockwise - negative rotation
Example: Consider the capital letter A.
A
a) Write the letter A after a 90 degree
counterclockwise rotation.
b) Write the letter A after a 90 degree clockwise
rotation.
c) Write the letter A after a 180 degree rotation.
y
x
y
C
A
B
x
y
E
D
F
x
y
G
H
J
I
x
Attachments
HW TRANSLATIONS #2.gsp
HW TRANSLATIONS #5.gsp
HW TRANSLATIONS #4.gsp
HW TRANSLATIONS #3.gsp