To be able to analyze and measure anglesusing a protractor . To be able to identify angles as rightangle, acute angle, obtuse angle, straight angle. To be able to learn what is angle is.
Angles can be measured in degrees orradians. For the time being, we will strictlytalk about angles in terms of their degree measure. The symbol for degrees is °.Angles can measure from 0°up to 360°. Angles with no measure are called zero angles, while angles of 360° are full rotations.
A An angles is a figure formed by two rays with common endpoint , and which are not on the same line. Two 1 B rays are called the sides of O the angle. The common endpoint of the sides of an angles is called the vertex.•In the figure above , rays OA and OB are the two sides of the angle.Point O is the vertex of the angle.
The measures of an angle refers to the opening made from one side ofthe angle to the other. An arrow from one side of the angle to the other usually denotes the particular measured desired. B 40 C
B 40 A C To use the protractor, place the center point of the protractor on the vertex of the angle to be measured. Line up the marked label 0 oneither scale with one side of the angle . In the figure above, the measure of angle BAC is 40 degrees.
•A right angle is an anglewhose measure is exactly 90° J 90 K L
•An acute angle is an anglewhose measure is less than90° A B E F C D
•Obtuse angles have measuresgreater than 90° but lessthan 180°. T U V Q S R
• if an angle’s measure is R180°, it is called astraight angle. 180 Q P
A. Identify what is being modified in FF. 1. An angle whose measure is exactly 90°. 2. A figure formed by two rays with common endpoint. 3. An angle whose measure is 180 degrees.4. an angle whose measure is less than 90°.5. angles have measures greater than 90° but less than 180°.
L M K J O N PA. Use your protractor to measure each angle in the given figure.1. Angle JOK 6. Angle KOL2. Angle KOM 7. Angle JOP3. Angle LON 8.Angle MOL4. Angle MOP 9. Angle MON5. Angle POL 10.Angle JOL
L M K J O N PB. (same figure) Tell what kind of angle is each.1. Angle JOK 6. Angle KOL2. Angle KOM 7. Angle JOP3. Angle LON 8.Angle MOL4. Angle MOP 9. Angle MON5. Angle POL 10.Angle JOL
A. B.1. 135 1. Obtuse angle2. 90 2. Right angle3. 90 3. Right angle4. 90 4. Right angle5. 135 5. Obtuse angle6. 45 6. Acute angle7. 135 7. Obtuse angle8. 45 8. Acute angle9. 45 9. Acute angle10. 90 10. Right angle