1. IM1 – G-CO-4 Lesson 3 Rotations Moving an Object In 2 Dimensions
Mr. Deyo
G.CO.4 Develop definitions of rotations, reflections, and translations in terms of angles, circles, perpendicular lines, parallel lines, and line segments.

2. Date:
Title: IM1 – G-CO-4 Lesson 2 Reflections
Learning Target
By the end of the period, I will create a definition of reflection in 2 dimensions and apply that definition to a given object.
I will demonstrate this by completing Four-Square Notes and by solving problems in a pair/group activity.

3. Home Work 1-2-3: 1) Class 4-Square Notes Put In Binder?
2) Section ______ 3) Section ______
TxtBk. Problems_________ Notes Copied on blank sheet Solved and Put in Binder? of paper in Binder?
Table of Contents
Date Description Date Due

4. Storm Check (Think, Write, Discuss, Report) Questions on which to ponder and answer:
How are the two images similar?
How are they different?
How can these two images be related to math?
IMAGE 1
IMAGE 2

5. Reflection Vocabulary
Pre-Image
Image
Axis of Reflection

6. Vocabulary Acquisition
Friendly Definition
Sketch
Wordwork
Sentence
DAY 2
1. Review word
Friendly Definition
Physical Representation
2. Draw a sketch
DAY 1
Use Visuals
Introduce the word
Friendly Definition
Physical Representation
Use Cognates
Write friendly definition
Word List
Vocabulary Acquisition
DAY 3 and/or DAY 4
1. Review the word
Friendly Definition
Physical Representation
2. Show how the word works
Synonyms/antonym
Word Problems
Related words/phrases
Example/non-example
DAY 5
1. Review the word
Friendly definition
Physical Representation
3. Write a sentence
at least 2 rich words (1 action)
correct spelling
correct punctuation
correct subject/predicate agreement
clear and clean writing

7. Orientation (flipped)
Notes:
REFLECTION (Flip): takes an image and makes a mirror image in a plane across a given axis of reflection
Reflections PRESERVE:
Size Shape
CHANGE:
Orientation (flipped)

8. Storm Check (Think, Write, Discuss, Report)
What is the difference between a translation and a reflection? A translation ____________________________ _______________________________________. A reflection _____________________________

9. ABCDE A’B’C’D’E’ (_____ , _____) (_____ , _____) (_____ , _____)
The BLUE pentagon is the PRE-IMAGE and the GREEN one is the IMAGE. How would you describe the reflection?
The IMAGE has reflected across ____________.
ABCDE
Coordinates for Point A
(_____ , _____) A B
Coordinates for Point A’
(_____ , _____) D E C
Coordinates for Point B
(_____ , _____) E’ D’ C’
Coordinates for Point B’
(_____ , _____) A’ B’
A’B’C’D’E’

10. ABCDE A’B’C’D’E’ (_____ , _____) (_____ , _____) (_____ , _____)
The BLUE pentagon is the PRE-IMAGE and the GREEN one is the IMAGE. How would you describe the reflection?
The IMAGE has reflected across ____________.
ABCDE
Coordinates for Point C
(_____ , _____) A B
Coordinates for Point C’
(_____ , _____) D E C
Coordinates for Point D
(_____ , _____) E’ D’ C’
Coordinates for Point D’
(_____ , _____) A’ B’
A’B’C’D’E’

11. Storm Check (Think, Write, Discuss, Report)
What rule for changes in coordinates would you create for reflections across the x-axis?
A reflection across the x-axis changes the original pre-image coordinates from (x, y) to
_______________________________________.
R x-axis(x, y)  (____ , ____)

12. (_____ , _____) (_____ , _____) (_____ , _____) (_____ , _____)
The BLUE triangle is the PRE-IMAGE and the GREEN triangle is the IMAGE. How would you describe the reflection?
The IMAGE has reflected across ____________.
ABC
A’B’C’
Coordinates for Point A
(_____ , _____) A A’
Coordinates for Point A’
(_____ , _____) B B’ C C’
Coordinates for Point B
(_____ , _____)
Coordinates for Point B’
(_____ , _____)

13. Storm Check (Think, Write, Discuss, Report)
What rule for changes in coordinates would you create for reflections across the y-axis?
A reflection across the y-axis changes the original pre-image coordinates from (x, y) to
_______________________________________.
R y-axis(x, y)  (____ , ____)

14. Reflection Vocabulary
Pre-Image
Image
Axis of Reflection

15. REFLECTION across y = x
y = x (a, b)  (b, a)

16. REFLECTION (Flip): There are 4 main axes of reflection:
x-axis (a, b)  (a, -b)
y-axis (a, b)  (-a, b)
y = x (a, b)  (b, a)
y = -x (a, b)  (-b, -a)

17. Date:
Title: IM1 – G-CO-4 Lesson 2 Reflections
Learning Target
By the end of the period, I will create a definition of reflection in 2 dimensions and apply that definition to a given object.
I will demonstrate this by completing Four-Square Notes and by solving problems in a pair/group activity.

18. Home Work 1-2-3: 1) Class 4-Square Notes Put In Binder?
2) Section ______ 3) Section ______
TxtBk. Problems_________ Notes Copied on blank sheet Solved and Put in Binder? of paper in Binder?
Table of Contents
Date Description Date Due