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Pre-Algebra with Pizzazz page 119 "Why is a Leaky Faucet Like a Race Horse?" (if available) Pre-Algebra with Pizzazz "How Do Bulldogs Get Flat Noses?" Page 122 (if available. 1-29-13 Measuring Angles and Special Angles EQ: How do you use a protractor to measure angles? . BOP and DWP.
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Pre-Algebra with Pizzazz page 119 "Why is a Leaky Faucet Like a Race Horse?" (if available) Pre-Algebra with Pizzazz "How Do Bulldogs Get Flat Noses?" Page 122 (if available
1-29-13 Measuring Angles and Special Angles EQ: How do you use a protractor to measure angles? BOP and DWP
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
RIGHT ANGLE An angle that measures 90 degrees.
ACUTE ANGLE An angle that measures less than 90 degrees
OBTUSE ANGLE An angle that measures greater than 90 degrees but less than 180 degrees.
STRAIGHT ANGLE An angle that measures 180 degrees.
COMPLEMENTARY ANGLES If the sum of the measures of two angles is 90 degrees, the angles are complementary.
SUPPLEMENTARY ANGLES If the sum of the measures of two angles is 180 degrees, the angles are supplementary.
CONGRUENT ANGLES Angles that have the same measure are congruent angles.
ADJACENT ANGLES Adjacent angles share a vertex and a side but no points in their interiors.
VERTICAL ANGLES Vertical angles are formed by two intersecting lines and are opposite each other. Vertical angles are congruent.
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.
HOW TO USE A PROTRACTOR http://www.youtube.com/watch?v=FeclDm7pVcI
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 A E B F 50° C 40° D CFB DFC and Possible answer: EFA and AFB Course 2 Insert Lesson Title Here Lesson Quiz 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.
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 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°,
If you draw three lines that all share a common point of intersection, how many Different pairs of vertical angles are formed?
Summary: Answer today’s essential question in three to four sentences. Homework: Vocabulary and work on ratio and proportion picture