2. Transparency 1 Click the mouse button or press the Space Bar to display the answers.

3. Splash Screen

4. Example 1-3b Objective Classify and draw angles

5. Example 1-3b Vocabulary Angle Two rays with a common endpoint form an angle. The rays and vertex are used to name the angle

6. Example 1-3b Vocabulary Degrees The most common unit of measure for angles. If a circle were divided into 360 equal-sized parts, each part would have an angle measure of 1 degree

7. Example 1-3b Vocabulary Vertex The common endpoint of the rays forming the angle

8. Example 1-3b Vocabulary Acute angle An angle with a measure greater than 0 0 and less than 90 0

9. Example 1-3b Vocabulary Right angle An angle that measures 90 0

10. Example 1-3b Vocabulary Obtuse angle Any angle that measures greater than 90 0 but less than 180 0

11. Example 1-3b Vocabulary Straight angle An angle that measures exactly 180 0

12. Lesson 1 Contents Example 1Classify Angles Example 2Classify Angles Example 3Draw an Angle

13. Example 1-1a Classify the angle as acute, obtuse, right, or straight. Answer: Straight angle Draw the angle 1/3 The angle looks like a straight line Straight line is 180 0 which meets the definition of a straight angle

14. Example 1-1b Classify the angle as acute, obtuse, right, or straight. Answer: right angle 1/3

15. Example 1-2a Classify the angle as acute, obtuse, right, or straight. Answer: Acute angle The angle is less than 90  2/3 Draw the angle Compare the angle to a 90 0 angle Meets the definition of an acute angle

16. Example 1-2b Classify the angle as acute, obtuse, right, or straight. Answer: obtuse angle 2/3

17. Example 1-3a Draw an angle with a measure of 140 . Classify the angle as acute, obtuse, right, or straight. Draw a ray. 3/3 Place the center of the protractor on the endpoint of the ray Make sure the ray is on the 0 0 of the protractor

18. Example 1-3a Draw an angle with a measure of 140 . Classify the angle as acute, obtuse, right, or straight. Make a hash mark at the 140 0 using the numbers from the 0 3/3 Remove protractor

19. Example 1-3a Draw an angle with a measure of 140 . Classify the angle as acute, obtuse, right, or straight. Using a straight edge, draw a ray from the endpoint of the first ray to the hash mark 3/3 To classify, compare to a 90 0 angle The angle is greater than 90  Meets the definition of an obtuse angle Obtuse angle Answer:

20. Example 1-3b Draw an angle with a measure of 60 . Classify the angle as acute, obtuse, right, or straight. Answer: acute angle * 3/3

21. End of Lesson 1 Assignment Lesson 10:1Angles9 - 20 All