Angles Angles formed by two rays with a

Angles

Angles �formed by two rays with a common endpoint �angles (∠��) are measured in degrees (⁰) �a protractor is used to measure angles

Kinds of Angles �

Kinds of Angles � 2. Right angles (∠�� – measure exactly 90⁰ � Examples:

Kinds of Angles � 3. Obtuse angles (∠�� )– measure more than 90⁰ but less than 180⁰ �Examples:

Kinds of Angles � 4. Straight angles (∠�� – measure exactly 180⁰ � Examples:

Kinds of Angles � 5. Reflex angles (∠��) – measure more than 180⁰ but less than 360⁰ � Examples:

Pairs of Angles � 1. Vertical Angles – two angles having a common point �Examples:

Pairs of Angles � 2. Adjacent angles – two angles with a common point and a common side �Examples:

Refer to the given figure. �Given: 1 = 34° �What kinds of angles are 1 and 2? 2 1 3 4

Refer to the given figure. �Given: 1 = 34° �What kinds of angles are 1 and 3? 2 1 3 4

Pairs of Angles � 3. Complementary Angles – two angles having a sum of 90⁰ C F C �Examples: B B A

Pairs of Angles � 3. Complementary Angles – two angles having a sum of 90⁰ �Examples:

Pairs of Angles � 4. Supplementary angles – two angles having a sum of 180⁰ �Examples:

Refer to the given figure. �Given: 1 = 34° �What is the supplement of 4? �What is the 2 1 measure of 4? 3 4

Refer to the given figure. �Given: 1 = 34° �What kinds of angles are 3 and 2? 2 1 3 4

EXERCISES

Exercises: A. Classify the following angles based on their measures. � 1. 145⁰ � 2. 55⁰ � 3. 20⁰

Exercises: Classify the following angles based on their measures. � 4. 90⁰ � 5. 78⁰ � 6. 170⁰

Exercises: B. What kind of angle is suggested by each of these? � 1. the open jaws of a dog � 2. an upright flagpole and the ground � 3. the hands of a clock at

Exercises: C. Find the complement of the following: � 1. 36⁰ � 2. 54⁰ � 3. 69⁰

Exercises: D. Find the supplement of the following: � 1. 100⁰ � 2. 67⁰ � 3. 143⁰

E. 48° 2 1 3 4

E. � 48° 2 1 3 4

E. � 48° 2 1 3 4

E. � 48° 2 1 3 4

E. � 48° 2 1 3 4