9.2 ­ Reflections.notebook
November 19, 2015
11/19: Warm Up
1. Does the transformation appear to be an isometry?
Explain.
2. Write a rule that describes the translation.
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9.2 ­ Reflections.notebook
November 19, 2015
9.2: Reflections
Date: 11/19
Reflections across a line r, called the line of symmetry, is a
transformation with these two properties:
1.
If a point A is on line r, then the image of A is itself
( ____________ )
2.
If a point B is not on line r, then r is the
_______________________ bisector of ______.
3.
A reflection across a line is an isometry.
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9.2 ­ Reflections.notebook
November 19, 2015
Ex 1). Consider point F(2, 6):
a) Reflect F over the line y = 3
b) Reflect A over the line x = ­2
c) Reflect B over the x­axis
d) Reflect C over the y­axis
e) Reflect D over the line y = x
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9.2 ­ Reflections.notebook
November 19, 2015
Ex 2). Use points: X(­4, 3), Y(2, 6), and Z(­1, ­6). What is the
image of Triangle XYZ reflected across the x­axis?
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9.2 ­ Reflections.notebook
November 19, 2015
Ex 3). Use points: X(1, ­3), Y(4, ­1), and Z(5, ­3).
a) Reflect Triangle XYZ across the line y = 1
b) Now reflect the image over the line x = ­1
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9.2 ­ Reflections.notebook
November 19, 2015
Ex 4). Use points: X(­2, 4), Y(­3, 1), and Z(­1, ­4).
a) Reflect Triangle XYZ across the line x = ­2
b) Now reflect the image across the y = x
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9.2 ­ Reflections.notebook
November 19, 2015
Ex 5). Use the points: X(­3, 0), Y(0, 5), Z(1, 2).
a) Reflect
b) Now reflect
across the x­axis
across the line x = 1
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9.2 ­ Reflections.notebook
November 19, 2015
Homework:
pg. 583 #1 – 3, 7 – 15, 18, 22 – 24
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9.2 ­ Reflections.notebook
November 19, 2015
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