Main Idea and New Vocabulary Key Concept Types
Main Idea and New Vocabulary Key Concept: Types of Angles Example 1: Name Angles Key Concept: Pairs of Angles Example 2: Real-World Example 3: Find a Missing Angle Measure
• Classify angles and identify vertical and adjacent angles. • congruent • obtuse angle • vertex • straight angle • acute angle • vertical angles • right angle • adjacent angles
Name Angles Name the angle below in four ways. Then classify it as acute, right, obtuse, or straight. • Use the vertex as the middle letter and a point from each side, FGH or HGF. • Use the vertex only, G. • Use a number, 2. Since the angle is less than 90°, it is an acute angle.
Name Angles Answer: FGH, HGF, G, 2; acute
Name the angle below in two ways. Then classify it as acute, right, obtuse, or straight. A. JKL, K; acute B. LKJ, K; right C. JKL, K; obtuse D. LKJ, J; obtuse
SEWING Identify a pair of vertical angles and adjacent angles in the diagram. Justify your response. Answer: 3 and 5 are vertical angles because they are opposite angles formed by intersecting lines. 4 and 5 are adjacent angles because they share a common side.
HIKING Identify a pair of vertical angles and adjacent angles in the diagram of the hiking trails. A. vertical: 5 and 7 adjacent: 5 and 8 B. vertical: 5 and 8 adjacent: 6 and 7 C. vertical: 6 and 7 adjacent: 5 and 8 D. vertical: 6 and 7 adjacent: 7 and 8
Find a Missing Angle Measure What is the value of y in the figure below? The angle labeled y and the angle labeled 60 are vertical angles. Since vertical angles are congruent, the value of y is 60. Answer: 60°
What is the value of x in the figure below? A. 14° B. 76° C. 104° D. 180°
- Slides: 13