Warm-Up
The quadrilateral is a parallelogram. Solve for x.
1.
2.
4𝑥 − 3
3𝑥 + 15
75
3𝑥 + 68
3.
3𝑥 + 6
5𝑥 − 28
Congruence
Transformations
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
A transformation moves or changes a figure to produce a
new figure called an image. Another name for the original
figure is the pre-image.
Transformations can be shown using an arrow.
(pre-image)
∆𝐴𝐵𝐶 → ∆𝐴′𝐵′𝐶′ (Image)
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
Congruence transformations preserve the size and shape of a
figure. They are also called an isometry.
There are three main types of congruence
transformations:
• A translation moves every point of a figure the same
distance in the same direction.
• A reflection uses a line of reflection to create a mirror
image of the original figure.
• A rotation turns a figure about a fixed point, called
the center of rotation.
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
EXAMPLE 1
Identify transformations
Name the type of transformation demonstrated in each picture.
b.
a.
Reflection
Rotation
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
EXAMPLE 1
Identify transformations
c.
Translation
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
Example 2
Name the type of transformation shown.
reflection
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
EXAMPLE 3
Identify transformations
Find the coordinates of the vertices of each figure after the given transformation.
Then draw the image.
N’(_____ , _____), R’(_____ , _____ ), J’(_____ , _____ )
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
EXAMPLE 4
Identify transformations
Find the coordinates of the vertices of each figure after the given transformation.
Then draw the image.
X’(_____ , _____),K’(_____ , _____),R’(_____ , _____),Q’(_____ , _____)
EQ: What are congruence transformations?
Demonstrated in writing in summary of notes.
Homework
• Review Cornell notes.
• Write up questions and summaries.
• Page 276-277 # 3-12, 17-19