Download Angle Relationships Lesson

Name: __________________________________________
Unit 1: Transformations and Angles
Date: ___________________________
Lesson #1: Identify Angle Relationships in Parallel Lines Cut By A Transversal
When two _____________________________________ lines are cut by a third line,
called the ______________________________________, some special angle relationships
are formed.
From our exploration we know that…
 1  _____________
 2  _____________
 5  _____________
 6  _____________
 1 +  2 = _____________
 1 +  3 = _____________
How many other angles are supplementary to  1? _______________________________
How many other angles are congruent to  1?_______________________________
CORRESPONDING ANGLES (WHEN YOU SLIDE ‘EM, THEY TAKE THE SAME SPOT!)
Since corresponding angles are the same shape and
1
3
5
7
2
4
6
8
same size, we know they are
___________________________________________.
That means their angle measures are
___________________________________________.
 1 corresponds to _______________
 5 corresponds to _______________
 2 corresponds to _______________
 6 corresponds to _______________
 3 corresponds to _______________
 7 corresponds to _______________
 4 corresponds to _______________
 8 corresponds to _______________
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Name: __________________________________________
Unit 1: Transformations and Angles
Date: ___________________________
Lesson #1: Identify Angle Relationships in Parallel Lines Cut By A Transversal
ALTERNATE INTERIOR ANGLES (A.I.A.)
Alternate Interior Angles are ______________________________.
“Alternate” refers to the angles being on ______________________________ sides of the transversal.
“Interior” refers to the angles being on the ______________________________ of the parallel lines.
Statement
Reason
A = 35
Given Information
D
A
H
E
A
C
B
G
F
≅ G
So, we can conclude that if two angles are alternate interior angles, their measures are the ____________.
ALTERNATE EXTERIOR ANGLES (A.E.A.)
Alternate Exterior Angles are ______________________________.
“Alternate” refers to the angles being on ______________________________ sides of the transversal.
“Exterior” refers to the angles being on the _______________________________ of the parallel lines.
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Name: __________________________________________
Unit 1: Transformations and Angles
Date: ___________________________
Lesson #1: Identify Angle Relationships in Parallel Lines Cut By A Transversal
Statement
Reason
C = 40
Given Information
D
A
H
E
C
C
B
G
F
≅ E
So, we can conclude that if two angles are alternate exterior angles, their measures are the ____________.
Example 1: Find Angle Measures of Parallel Lines Cut by Transversals
In the figure, line a
line b. Find the measure of each angle.
What is the measure of  4?
What is the measure of  3?
What is the measure of  5?
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Name: __________________________________________
Unit 1: Transformations and Angles
Date: ___________________________
Lesson #1: Identify Angle Relationships in Parallel Lines Cut By A Transversal
You Try 1!
In the figure, line m
line l. Find the measure of each angle.
What is the measure of  4?
What is the measure of  2?
What is the measure of  6?
How many different angles would be formed by a transversal intersecting three parallel lines? How many
different angle measures would there be?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Explain how a transversal could intersect two other lines so that corresponding angles are not congruent.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Can you think of two real-world examples of parallel lines? How are these examples different from the
mathematical concept of parallel lines?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
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Name: __________________________________________
Unit 1: Transformations and Angles
Date: ___________________________
Lesson #1: Identify Angle Relationships in Parallel Lines Cut By A Transversal
Exit Ticket:
1. Name all angles congruent to  3.
2. Name all the angles supplementary to  6.
3. If m  1 = 105, what is the m  3?
4. If m  5 = 120, what is the m  2?
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