Download Angle Protractor Postulate

PAP Geometry: Unit 1 – Measurements of Angles
1.4 Student Notes – Measurements of Angles
Pages 16-21
Definition
Diagram
Angle
Angle Names
R
Protractor
Postulate
S
1
T
Find the measure of each angle, then classify the angle.
B
Measurement
Example
1:
Example
2:
Example
3:
C
Classify
m∠AOB =
A
m∠BOC =
m∠AOC =
O
Using a protractor, measure each angle and write a measure statement.
Example 4: ________________________
Example 5: _________________________
X
Y
A
Z
C
B
Draw five points, A, B, C, D, and E so that all three statements are true.
Example 6:
∠DBE is a straight angle.
∠DBA is a right angle.
∠ABC is a straight angle.
Example 7:
C is in the interior of ∠ADE.
m∠ADC + m∠CDE =
120o .
∠CDB is a straight angle.
PAP Geometry: Unit 1 – Measurements of Angles
Definition
Diagram
A
Congruent
Angles
D
C
B
Angle
Addition
Postulate
E
F
Q
T
R
S
Angle
Bisector
C
A
B
D

Example 8: AT is on the interior of ∠MAH . m∠MAT =(2 x + 7)o , m∠TAH =
( x + 15)o ,
m∠MAH =(4 x − 6)o , find m∠MAT and m∠MAH .
Statements
Reasons

1. AT is on the interior of
∠MAH .
1.
2.
2.
3.
3. Substitution Property
4.
4. Combine like terms/Simplify
5.
5.
6.
6.

Example 9: OH bisects ∠JON . If m∠JOH =(2 x + 12)o and m∠JON =(5 x − 12)o , find m∠HON .