1. Measure and classify Angles
Geometry Section 1.4
Measure and classify Angles

2. Terms Angle consists of two different rays with the same endpoint
vertex
side

3. To name angles, either name with 3 points (point at the vertex in the middle), or name with the vertex point.
See mimio example
To measure use protractor

4. Classifying angles
Acute angle measures more than 0 degrees, but less than 90 degrees
Right angle measures 90 degrees
Obtuse angle measures more than 90 degrees but less than 180 degrees
Straight angle measures 180 degrees

5. Angle Addition Postulate
If P is in the interior of angle RST, then the measure of angle RST is equal to the sum of angle PST and angle RST
See mimio example

6. Examples
Page 29
Problems #23, 25

7. Terms Two angles are congruent if they have the same measure
Angle bisector is a ray that divides an angle into two angles that are congruent

8. Examples
Page 30
Problem 41

9. Assignment
Section 1.4
Page 28
Problems # 4, 8 – 40 even,