Page 88 - Math Course 2 (Book 2)
P. 88
Transformations: Rotated Images
indirect isometry First reflect parallelogram WXYZ in line p.
orientation is not preserved - the order of the Then label the image W'X'Y'Z'.
lettering is reversed, either clockwise becomes
counterclockwise or counterclockwise becomes Next, reflect the image in line q. Then label the
clockwise. image W’’X’’Y’’Z’’.
1 C Parallelogram W’’X’’Y’’Z’’ is the
B Answer image of parallelogram WXYZ
under reflections in line p and q.
A 0 1 2 3
Identifying Rotational Symmetry
A’
–1
C’ Example
B’
1 C
B QUILTS
C’ Identify the order and magnitude of the symmetry
in the medium star directly to the left of the large
A 0 1 2 3 star in the center of the quilt made by Judie
Mathieson.
B’
–1
A’
Let’s Begin
Reflections in Intersecting Lines
Example
Find the image of parallelogram WXYZ under
reflections in line p and then line q.
W
X The medium star directly to the
Answer left of the large star in the center
Z has rotational symmetry of order
Y P 16 and a magnitude of 22.5°.
Y’
Z’’ Identify the order and magnitude of the symmetry
X’ in the tiny star above the medium-sized star
W’’ identified in Example 3a.
Z’
Y’’ W’ q Answer The tiny star has rotational
symmetry of order 8 and
magnitude of 45°.
X’’
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