1. Supplementary Angles
Supplementary Angles are two angles that together add up to 180 degrees. *The angles do not have to be next to each other to be supplementary.
For example 45 degrees and 135 degrees add up to 180 degrees so they are supplementary angles.
45 degrees degrees = 180 degrees

2. Complementary Angles
Complementary Angles are two angles that add up to 90 degrees.
For example 20 degrees and 70 degrees add up to 90 degrees. *The angles do not have to be next to each other to be complimentary.
= 90 degrees

3. Vertical Angles
Vertical Angles are the angles opposite each other when two lines cross.
The two opposite angles are equal with respect to degrees. It creates to pairs of vertical angles.
135

4. Vertex
A vertex is the point where two or more straight lines meet each other. See example below.
The vertex
occurred where the 3
lines met each other. B A D C

5. Adjacent Angles
Adjacent Angles are two angles that share a common side and vertex but do not overlap. B A C D

6. Practice Write a simple equation for a complementary angle.
Write a simple equation for a supplementary angle.
Explain in your own words what a vertex is.
Explain in your own words what a vertical angle is.

7. Practice
Identify two complementary angles, two supplementary angles, two vertical angles. Identify one vertex.
135 C B E D A

8. Practice
Find the missing angle. * Remember that the vertical angles will add up to 360 degrees. This will help you.
Is there a complementary angle in this case?
Is there a supplementary angle in this case?
Why or why not? ?
140 C B E D A