Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
8-3 Rotations
A rotation is a transformation that turns a figure about a
fixed point.
That fixed point is called the center of rotation
A figure has rotational symmetry if it can be rotated 180 or
less and exactly matches its original figure.
The angle of rotation is the number of degrees the figure
rotates. One full rotation is 360.
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
Tell whether the figure has rotational
symmetry. If so, give each angle and direction
of rotation that produce rotational symmetry.
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
c.
d.
e.
f.
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
Coordinate Rules for Rotation - Counterclockwise
(x, y)
y
** Same rule for 270
clockwise rotation**
x
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
∘
270 Counterclockwise Rotation
** Same rule for 90 clockwise
rotation** (x, y)
y
x
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
Original Image
(x, y)
P(0, 2)
Q(2, 4)
R(1, 1)
(-y, x)
Objective: To graph rotations in the coordinate plane and identify rotational symmetry.
Example 3:
( x , y)
(
,
A' (
,
)
A ( -5, 2)
A' (
,
)
B ( -6, -1) B' (
,
)
B ( -6, -1) B' (
,
)
D ( -2, 1)
, )
D ( -2, 1)
, )
A ( -5, 2)
D' (
)
( x , y)
A
D' (
A
D
B
( , )
D
B
BACK: Write this on your card.
8-3
Rotations
• 270 counterclockwise (90 clockwise)
ORIGINAL
IMAGE
(x, y)
(y, -x)
• 90 counterclockwise (270 clockwise)
ORIGINAL
(x, y)
• 180
ORIGINAL
(x, y)
IMAGE
(-y, x)
IMAGE
(-x, -y)
FOLD