1. ANGLES, ANGLES, ANGLES Naming Angles Measuring Angles Classifying Angles The Angle Addition Postulate

2. An angle is formed by two rays with a common endpoint called a vertex. C - vertex D E CD and CE are the rays that form the sides of the angle. C is the common endpoint, or vertex.

3. There are four different ways to name an angle: #1: -by its vertex with  in front of the capital letter C D E This is  C.

4. There are four different ways to name an angle: #2: -by a number placed inside the angle with  in front of the number C D E This is  3. 3

5. There are four different ways to name an angle: #3: - by three letters - a point on one of the rays followed by the vertex of the angle followed by a point on the other ray with  in front the three capital letters. C D E This is  DCE or  ECD.

6. There are four different ways to name an angle: #4: -by a lower case letter placed inside the angle with  in front of the lower case letter. C D E This is  a. a

7. Click on the correct name for the angle shown. T E J DD d  TEJ  JTE  etj

9. Think about capital letters and lower case letters. Think about what the middle letter should be.

10. WHITE NOTE CARD: ANGLES Formed by two rays with a common endpoint called a vertex. BC and BG are the rays, B is the vertex Named by: - the vertex (a capital letter)  B - a number placed inside the angle  8 - three capital letters - a point on one ray followed by the vertex followed by a point  CBG on the other ray; vertex always in the middle  GBC - a lower case letter placed in side the angle All of these start with . B C G 8

11. Angles are measured in degrees using a protractor. The protractor is used to measure the opening between the two rays that make up the angle.

12. Angles can be classified in four different ways: Acute angles - angles that measure less than 90º Right angles - angles that measure 90º Obtuse angles - angles that have a measure greater than 90º but less than 180º Straight angles - angles that measure 180º

13. True or False - Click true or false next to each statement. TRUE / FALSE - All right angles are congruent. TRUE / FALSE - All obtuse angles are congruent. TRUE / FALSE - An obtuse angle and an acute angle could be congruent. TRUE / FALSE - Three acute angles could be congruent. Continue – all finished with the True / False questions.

16. WHITE NOTE CARD: ANGLE CLASSIFICATION Angles can be classified in four different ways: Acute angles - angles that measure less than 90º Right angles - angles that measure 90º Obtuse angles - angles that have a measure greater than 90º but less than 180º Straight angles - angles that measure 180º

17. If R is in the interior of  PQS, then m  PQR + m  RQS = m  PQS. Q P S R

18. If R is in the interior of  PQS, then m  PQR + m  RQS = m  PQS. Q P S R So, if R is in the interior of the big angle, then the sum of the measures of the two smaller angles will equal that big angle.

19. If R is NOT in the interior of  PQS, then m  PQR + m  RQS  m  PQS. Q P S R

20. If m  PQR + m  RQS = m  PQS, then R is in the interior of  PQS. What does this mean? Think about the second part of the Segment Addition Postulate.

21. COLORED NOTE CARD ANGLE ADDITION POSTULATE If R is in the interior of  PQS, then m  PQR + m  RQS = m  PQS. If m  PQR + m  RQS = m  PQS, then R is in the interior of  PQS. Q P S R