1. 1.3 Warm-Up Daily Agenda Reflection across the y-axis B B′ 𝐴 𝐴′ C′ C
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 3
Daily Agenda 𝐴 C B 𝐴′ C′ B′
Reflection across the y-axis

2. Unit 1: Transformations in the Coordinate Plane
1.3 Reflections

3. 1.3 Reflections Daily Agenda
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
A reflection is a transformation that flips a figure across a line called a ______ ____ ____________.
line of reflection
flip
line of
reflection
isometric
orientation

4. 1.3 Reflections Daily Agenda x-coordinate (−𝒙, 𝒚) y-coordinate (𝒙, −𝒚)
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
x-coordinate
(−𝒙, 𝒚)
y-coordinate
(𝒙, −𝒚)

5. 1.3 Reflections Daily Agenda swap (𝒚, 𝒙) opposite sign swap (−𝒚, −𝒙)
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
swap
(𝒚, 𝒙)
swap
opposite sign
(−𝒚, −𝒙)

6. 1.3 Reflections Daily Agenda
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
To reflect through the origin, the sign of the x and y coordinates _________.
change
The function for a reflection through the origin is 𝑅 0, 0 𝑥,𝑦 = _________
(−𝒙, −𝒚)

7. 1.3 Reflections Daily Agenda 𝑿’ 𝟐,𝟏 𝒀 ′ −𝟒, 𝟑 𝒁’ 𝟑,−𝟐 𝑹’ 𝟐,−𝟐 𝑺 ′ 𝟎,𝟓
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
𝑿’ 𝟐,𝟏
𝒀 ′ −𝟒, 𝟑
𝒁’ 𝟑,−𝟐
𝑹’ 𝟐,−𝟐
𝑺 ′ 𝟎,𝟓
𝑻’ −𝟏,𝟑
𝑺’ −𝟑,𝟒
𝑻 ′ −𝟑,𝟏
𝑼’ 𝟐,𝟏
𝑽’(𝟐,𝟒)

8. 1.3 Reflections Daily Agenda multiply x y (2a – x, y) x multiply y
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
multiply x y
(2a – x, y) x
multiply y
(x, 2b – y)

9. 1.3 Reflections Daily Agenda 𝑨’ −𝟏,−𝟑 𝑩 ′ −𝟓,−𝟑 𝑪’ −𝟒,−𝟒 𝑫’(−𝟐,−𝟒)
What are we learning today?
MGSE9 – 12.G.CO.4 - Experiment with transformations in the plane
What am I going to do?
Transformations in the Coordinate Plane
How will I show you I learned it?
Daily Exit Tickets
What’s for homework?
Booklet pg. 5
Daily Agenda
𝑨’ −𝟏,−𝟑
𝑩 ′ −𝟓,−𝟑
𝑪’ −𝟒,−𝟒
𝑫’(−𝟐,−𝟒)
𝑷’ 𝟎,𝟐
𝑸 ′ 𝟏,𝟎
𝑹’ −𝟏,−𝟓
𝑫’ −𝟏,−𝟏
𝑬 ′ −𝟐,−𝟑
𝑭’ −𝟒,−𝟐

10. Reflect the figure with the given vertices across the given line.1.
Reflect over the x-axis
A (1, 2)
B (3, 6)
C (5, 4) 2.
Reflect over the y-axis
D (-6, -1)
E (-2, -1)
F (-2, -4) 3.
Reflect over the y = x
G (-4, 3)
H (0, 4)
I (2, 2)
J (-1, 1)
Classwork Working independently or with one other person, complete the problems and hand in before the end of class. 4.
Reflect over the y = 3
K (-6, -1)
L (-6, 1)
M (-2, 1)
N (-2, -1)
O (-3, -3) 5.
Reflect over the x = 4
P (-2, -4)
Q (-1, 1)
R (2, 1)
S (-2, 4)