1. Unit 4A – Geometric Figures Lesson 1 Classify Angles
Unit 4 Geometry
Unit 4A – Geometric Figures
Lesson 1
Classify Angles

2. Lesson 1: Classify Angles
Objective: Swbat classify angles. Do Now: Quick Check

3. Lesson 1: Classify Angles
Definitions Vertex is the point where the two rays meet. Right Angle is exactly 90°. Acute Angle less than 90°. Obtuse Angle is greater than 90°. Straight Angle is exactly 180°. Congruent angles have the same measure. Vertical Angles are opposite angles formed by intersecting lines and are congruent. Adjacent angles share a common vertex and side.

4. Lesson 1: Classify Angles
Angles can be named several ways: - use the vertex as the middle letter and a point from each ray - use the vertex only - use a number <XYZ or <ZYX X <Y 1 Y <1 Z Classify: acute

5. Lesson 1: Classify Angles
Name each angle and classify.
A b. T
B C R S

6. Lesson 1: Classify Angles
Intersecting Lines form vertical and adjacent angles. 2 4
Vertical Angles Adjacent Angles < < <1 and <2
< < <2 and <3
<3 and <4
<1 and <4

7. Lesson 1: Classify Angles
Find the value of x.
2x + 2
130
Since vertical angles are equal then 2x + 2 = 130
Solve for x:

8. Lesson 1: Classify Angles
Find the value of x.
115° 5x
Since the adjacent angles form a straight line then
5x = 180
Solve for x:
What is the measure of each angle?

9. Classwork Guided Practice #1 – 4 Independent Practice #1 – 11
Problem Solving Practice #1 - 6

10. Closure Question: What are the four types of angles? Exit Ticket
Homework: Practice #1 - 14

11. Exit Ticket
Find the value of x. 12x

12. Homework