traingles

1. ANGLES

2. A
B
C
Naming An Angle
5

3. There are four main types of angles.
Straight angle
180o
Right angle
90o
Acute angle
Less than 90o
Obtuse angle
More than 90o
A
B C
A
B C
A
B C
B
A C
Types Of Angles

4. Two angles that have the same measure are called congruent
angles.
Congruent angles have the same size and shape.
A
B
C
300
D
E
F
300
D
E
F
300
Congruent Angles

5. Adjacent Angles
Two angles that have a common vertex and a common ray
are called adjacent angles.
C
D
B
A
Common ray
Common vertex

6. Vertical Angles
Vertically opposite angles are pairs of angles formed by two
lines intersecting at a point.
A
D
B
C
P
Vertically opposite angles are congruent.

7. Complementary Angles add up to 900
600
A
B
C
300
D
E
F
Complimentary Angles

8. Supplementary angles add up to 1800
They will typically form a straight angle together
R
Q
P
A
B
C
1000
800
Supplementary Angles

9. A line that intersects two or more lines at different points is
called a transversal.
(transversal)
B
A
D
C
P
Q
G
F
Pairs Of Angles Formed by a Transversal

10. Corresponding Angles
Corresponding angles are angles in the same spot in both
lines
Corresponding pairs of angles are congruent.
GPB = PQE
GPA = PQD
BPQ = EQF
APQ = DQF
Line M
B
A
Line N
D E
L
P
Q
G
F
Line L

11. Alternate Interior Angles
Alternate interior angles are formed on opposite sides of the
transversal on the inside of the lines.
Line M
B
A
Line N
D E
L
P
Q
G
F
Line L
BPQ = DQP
APQ = EQP
Alternate interior angles are congruent.

12. Alternate Exterior Angles
Alternate exterior angles are formed on opposite sides of the
transversal and on the outside of the lines.
B
A
D E
L
P
Q
G
F
BPG = DQF
APG = EQF
Alternate exterior angles are congruent.