Unit 1A – Angle Measure (Notes)
Name:
Objective(s):
Key Concepts
Date:
Essential Question(s):
Notes
degree
 definition
ray
 What does it look like?
 How is it named?
Opposite ray = straight angle
 definition
angle
 formal definition
 parts of an angle
There are FOUR ways to name an angle:
 What does it look like?
 How is it named?
 How does an angle divide the
coordinate plane?
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Key Concepts
Notes
Example 1
a) Name all angles that have B
as a vertex
a)
b) Name the sides of ∠5
b)
c) Write another name for ∠6
c)
d) Name the vertex of ∠4
d)
e) Name the sides of ∠7
e)
f) Write another name for
∠EBG
f)
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Key Concepts
Notes
Example 2
a) Name all angles that have
W as a vertex
a)
b) Name the sides of 1
b)
c) What are four other ways
to write  WYZ?
c)
Types or Classifications of
Angles
 Right
 Acute
 Obtuse
Congruent Angles
 Definition

What do they look like?

How is it written?
Angle bisector
 Definition
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Key Concepts
Notes
Example 3
a) Name two angles that are
congruent
a)
b) Name two angles that are
not congruent
b)
c) Name the straight angle
c)
Example 4
Given:
and
are opposite
rays, and
bisects
a) If m <RQT = 6x + 5 and m
<SQT = 7x – 2, find m <RQT.
a)
b) Find m <TQS if m <RQS = 22a
– 11 and m <RQT = 12a – 8.
b)
Summary, Reflection, & Analysis
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Unit 1A – Angle Measure
Construction – Copy an Angle
Name
Date
You can construct an angle congruent to a given angle without knowing the measure of an
angle.
Construction – Copy an Angle
1. Draw an angle on your paper and label it P on your paper. Below P, use a
straightedge to draw a ray on your paper and label its endpoint T.
2. Place the tip of the compass at point P and draw a large arc that intersects both sides
of P. Label the points of intersection Q and R.
3. Using the same compass setting, place the compass at point T and draw a large arc
that intersects the ray. Label the point of intersection S.
4. Place the point of your compass on R and adjust so that the pencil tip is on Q.
5. Without changing the setting, place the compass at S and draw an arc to intersect
the larger arc you drew in Step 3. Label the point of intersection U.
6. Use a straightedge to draw line TU.
Conclusion:
P _________ UTS
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Unit 1A – Angle Measure
Construction –Bisect an Angle
Name
Date
You can construct the angle bisector of any angle without knowing the measure of the
angle.
Construction – Bisect an Angle
1. Draw an angle on your paper and label the vertex as point A. Put your compass at
point A and draw a large arc that intersects both sides of A. Label the points of
intersection B and C.
2. With the compass at point B, draw an arc in the interior of the angle.
3. Keeping the compass the same setting, place the compass at point C and draw an arc
that intersects the arc drawn in Step 2.
4. Label the point of intersection point D. Draw line AD. Line AD is the bisector of A.
Conclusion:
mBAD _________ m DAC, therefore, BAD _________ DAC
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Unit 1A -Section 4: Angle Measure
Assignment #1
Name: ________________________
Date: ______________
Must show ALL Work
For Exercises 1-10, use the figure to the right.
Name the vertex of each angle.
1.
2.
3. 3.
4. 4.
Name the sides of each angle.
5.
6.
7.
Write another name for each angle.
8.
9.
10.
For Exercises 11-15, use the figure to the right.
Write another name for each angle.
11.
12.
13.
14.
15.
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For Exercises 16 and 17, use the figure to the right and the given information.
bisects
, and
and
are opposite rays.
16. If
and
find the value of x
17. If
find
and
For Exercises 18 -20, use the figure to the right and the given information.
and
are opposite rays,
bisects
and
bisects
18. If
19. If
20. If
and
, find
and
, find
and
.
, find
A five-pointed star sticker is shown below right with vertices labeled.
21. Find
and
if
.
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Unit 1A -Section 4: Angle Measure
Assignment #2
Name: __________________
Must show ALL Work
For Exercises 1 - 5, use the figure to the right and the given information.
and
are opposite rays,
bisects
, and
bisects
.
1-4: Write another name for each angle.
1.
2.
3.
4.
5. Name all sets of congruent angles.
6.
7. If
8. If
Page 9
. Explain why in complete sentences.
and
, find
.
.
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For Exercises 9 – 12, use the figure to the right.
9. Name at least one right angle.
10. Name at least two different acute angles.
11. Name at least one obtuse angle.
12. Name two angles that make a right angle together.
For Exercises 13 and 14, use the figure to the right and
the given information.
and
are opposite rays,
bisects
, and
bisects
.
13. If
.
14. If
.
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