1. Objective: To recognize and classify angles and
Their parts
Class Notes Geometry Sec 2.1
An Angle is made of 2 rays that share a common
endpoint
Side 1
Vertex
Side 2

2. There are 4 types of angles
a. Acute Angle – less than 90
b. Obtuse Angle – more than 90
c. Right Angle – exactly 90
d. Straight Angle – exactly 180

3. Complementary Angles are 2 angles whose
measures add up to 90.
Do these 2 angles appear to
Be complementary?
Right Angle = 90
Flash
4. Determine if two angles with the measures given
are complementary.
b. 27 & 73
a. 30 & 60
c. 11 & 79
d. 46 & 44
f. 36 & 54
e. 2 & 88

4. 5. Supplementary Angles are 2 angles whose
measures add up to 180.
Straight Angle = 180
Do these 2 angles appear to
Be supplementary?
Flash
6. Determine if two angles with the measures given
are supplementary.
b. 117 & 63
a. 30 & 150
c. 128 & 62
d. 86 & 104
f. 136 & 34
e. 2 & 178

5. 1 & 2 are adjacent angles
7. Intersecting lines
When 2 lines intersect 4
Angles are formed 2 1
1 & 2 are adjacent angles 3 4
1 & 3 are nonadjacent angles
1 & 2 are a linear pair and must = 180
1 & 3 are vertical angles and are congruent (equal)
Flash
Name another linear pair.
Name another linear pair.
Name another linear pair.
Name another pair of vertical angles.
A linear pair has a total measure of __________
Vertical Angles are __________