170 likes | 341 Views
7-2. Angles. Course 2. Learn to identify angles and parts of angles. 7-2. Angles. A. Vertex. 1. B. C. Course 2. An angle is formed by two rays with a common endpoint. The two rays are the sides of the angle. The common endpoint is is the vertex.
E N D
7-2 Angles Course 2 Learn to identify angles and parts of angles.
7-2 Angles A Vertex 1 B C Course 2 An angleis formed by two rays with a common endpoint. The two rays are the sides of the angle. The common endpoint is is the vertex. You can name an angle in three ways: • with the capital letter at the vertex: B, •with the number inside the angle: 1, •with three capital letters so that the letter at the vertex is in the middle: CBA ABC or
7-2 Angles The measure of XYZ is 122°, or m XYZ = 122°. Course 2 Angles are measured in degrees (°). You can use a protractor to measure an angle.
7-2 Angles STV m STV = 55° A. XTU B. m XTU = 25° Course 2 Additional Example 1A & 1B: Identifying Angle Measures Give the measurement of each angle.
7-2 Angles WTU C. STX D. m STX = 155° m STX = 55° + 60° + 40° m WTU = 40° + 25° m WTU = 65° Course 2 Additional Example 1C &1D: Identifying Angle Measures Give the measurement of each angle.
7-2 Angles STV m STV = 35° A. W V XTU B. X 50° 55° S U 35° 40° T m XTU = 40° Course 2 Insert Lesson Title Here Try This: Example 1 Give the measure of each angle.
7-2 Angles W V X 50° 55° WTU C. S U 35° 40° STX D. T m STX = 140° m STX = 35° + 55° + 50° m WTU = 90° m WTU = 50° + 40° Course 2 Insert Lesson Title Here Try This: Example 1 Continued Give the measure of each angle.
7-2 Angles Course 2 An angle’s measure determines the type of angle it is. A right angle is an angle that that measures exactly 90°. The symbol indicates a right angle An acute angle is an angle that measures less than 90° Anobtuse angle is an angle that measures more than 90° but less than180° A straightangle is an angle that measures 180°
7-2 Angles Course 2 Additional Example 2: Classifying Angles Tell whether each angle is acute, right, obtuse or straight. A. B. C. right angle acute angle obtuse angle
7-2 Angles Course 2 Insert Lesson Title Here Try This: Example 2 Tell whether each angle is acute, right, obtuse, or straight. B. C. A. straight angle obtuse angle acute angle
7-2 Angles Course 2 If the sum of the measures of two angles is 90°, then the angles are complementary angles. If the sum of the measures of two angles is 180°, then the angles are supplementary angles.
7-2 Angles m OMP = 30° and m OMR = 60° N Q 60° 90° P OMP and OMR are complementary. M 30° O 60° R Course 2 Additional Example 3A: Identifying Complementary and Supplementary Angles Use the figure to name the following. A. one pair of complementary angles Since 30° + 60° = 90°,
7-2 Angles m RMO = 60° and m QMO = 90° + 30° = 120° N Q 60° 90° P Since 60° + 120° = 180°, M 30° O 60° R RMO and QMO are supplementary. Course 2 Additional Example 3B: Identifying Complementary and Supplementary Angles Use the figure to name the following. B. one pair of supplementary angles
7-2 Angles m OMP = 30° and m NMQ = 60° N Q 60° 90° P OMP and NMQ are complementary. M 30° O 60° R Course 2 Try This: Example 3A Use the figure to name the following. A. one pair of complementary angles Since 30° + 60° = 90°,
7-2 Angles m QMP = 90° and m PMR = 30° + 60° = 90° N Q 60° 90° P Since 90° + 90° = 180°, M 30° O 60° R QMP and PMR are supplementary. Course 2 Try This: Example 3B Use the figure to name the following. B. one pair of supplementary angles
7-2 Angles A E B F 50° C 40° D CFB DFC and Possible answer: EFA and AFB Course 2 Insert Lesson Title Here Show what you know Give the measure of each angle, and tell whether it is acute, obtuse, right, or straight. AFB 90°; right 1. 140°; obtuse AFC 2. 3. DFC 40°; acute 4. Name a pair of complementary angles. 5. Name a pair of supplementary angles.
Classwork • Pg. 350 #10-18