1. Opening Activity #1 Turn in your Are You Ready?. #2 Have a pencil out & complete your progress tracker for your Ch. 7 pretest. #3 Go to xtramath.org and complete your program for the day. #4 Work on an early finisher.

2. Chapter 7 Lesson 1 Classify Angles Objective: Students will classify angles and identify vertical and adjacent angles.

3. Two angles are vertical if they are opposite angles formed by the intersection of two lines. Vertical angles are congruent or have the same measure. 1 2 3 4 Vertical Angles: or

4. Two angles are adjacent if they share a common vertex, a common side, and do not overlap. 1 2 3 4 Adjacent Angle Pairs:

5. Example 1: Name the angle in four ways. Then classify it as acute, right, obtuse, or straight. R S T 3 Obtuse To name angles, you can use the middle letter and a letter from each side (with the middle letter in the middle), use the middle letter, the vertex, only, or use a number. Remember: An obtuse angle is an angle greater than 90 degrees, an acute angle is an angle less than 90 degrees and a right angle equals 90 degrees.

6. Example 2: Name the angle in four ways then classify it as acute, right, obtuse, or straight. A B C 2 Right

7. Example 3: Name the angle in four ways. Then classify it as acute, right, obtuse, or straight. L M N 4 straight

8. Example 4: Identify a pair of vertical angles and adjacent angles in the diagram. 1 2 3 4 Vertical: Adjacent:

9. You can use what you learned about vertical and adjacent angles to find the value of a missing measure: Exampl e 5: The two angles (2x+2) and 130 are vertical angles so they are congruent so (2x+2)=130 2x + 2 = 130 -2 -2 2x = 128 x = 64

10. Example 6: What is the value of x in the figure? 3x + 60 = 90 -60 -60 3x = 30 x = 10 The box in the angle indicates that this angle equals 90 degrees.

11. Building on the Essential Question: Describe the difference between vertical angles and adjacent angles. Sample Answer: Vertical angles are opposite angles formed by the intersection of two lines. Adjacent angles can be formed by the intersection of two lines but must share a common side and vertex.