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.
Lesson 1: Classify 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
Lesson 1: Classify Angles Name each angle and classify. a. A b. T 2 B C R 3 S
Lesson 1: Classify Angles Intersecting Lines form vertical and adjacent angles. 1 Vertical Angles <1 <3 <2 <4 2 4 3 Adjacent Angles <1 and <2 <2 and <3 <3 and <4 <1 and <4
Lesson 1: Classify Angles Find the value of x. 2 x + 2 130 Since vertical angles are equal then Solve for x: 2 x + 2 = 130
Lesson 1: Classify Angles Find the value of x. 115° 5 x Since the adjacent angles form a straight line then 5 x + 115 = 180 Solve for x: What is the measure of each angle?
Classwork • Guided Practice #1 – 4 • Independent Practice #1 – 11 • Problem Solving Practice #1 - 6
Closure Question: What are the four types of angles? Exit Ticket Homework: Practice #1 - 14