9.3 ­ Classifying Angles
Objective:
Classify angles and find angle
measures.
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1

Right Angle
Acute Angle
Obtuse Angle
Straight Angle
2

Right Angle
­ any angle whose
measure is exactly
90 degrees.
3

Acute Angle
An angle whose measure is
less than 90 degrees.
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4

Obtuse Angle
An angle whose measure is
between 90 and 180 degrees.
5

Straight Angle
An angle whose measure
is exactly 180 degrees.
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6

Your Turn:
In your math notes and with your group work on
PAGE 430 Problems 1 ­ 4
7

Vertical Angles
A
­ Angles opposite each other.
B
­ Have equal measures.
Angle A = 135 degrees
Angle B =
8

Complementary Angles
­ Two angles whose sum
of their measures is 90 degrees.
es
re
eg
0 d es
re
6
eg
d
30
9

Supplementary Angles
­ Two angles whose sum
of their measures is
180 degrees.
120 degrees
60 degrees
10

Your Turn:
In your math notes and with your group work on
PAGE 431 Problems A & B
11