3. ANGLE
A FIGURE FORMED BY TWO NONCOLLINEAR RAYS WITH A COMMON ENDPOINT.

4. ANGLE
The TWO NONCOLLINEAR RAYS (ray BP & ray BC) are the SIDES of an angle.

5. ANGLE
The point where the rays intersect is called the VERTEX of an angle.

6. ANGLE MNEMONIC
S- Sides are 2 non-collinear rays.
E- Endpoint is also called vertex.
R- Rays are the 2 sides.
V- Vertex is the common endpoint.

7. AN ANGLE SEPARATES A PLANE INTO 3 PARTS
INTERIOR ANGLE- point D
EXTERIOR ANGLE – point H
THE ANGLE ITSELF
P, A, W,C ●H ●D

8. EXAMPLES

9. NAMING AN ANGLE

10. USING 3 POINTS. EXAMPLE: ABC orCBA PBW or WBP
An angle is named by:
USING
3 POINTS.
EXAMPLE:
ABC orCBA
PBW or WBP

11. An angle is named by:
2. BY THE VERTEX ALONE.
EXAMPLE: B

12. An angle is named by:
3. BY USING A NUMERAL.
EXAMPLE: 1 1 1

13. EXERCISES 3 2 1

14. NAME THE ANGLES USING 3 POINTS
NAME THE ANGLES USING A NUMERAL 3 2 1

15. WHAT ARE THE SIDES OF ANGLE 3.
ANOTHER NAME OF ANGLE 1.
B or ABW PBC or ABC
Segment AC and ray AP 3 2 1

16. WHAT IS THE COMMON SIDE OF 2 AND 3?
Segment AC 3 2 1

17. Name angles Name the three angles in the diagram. EXAMPLE 5
WXY, or YXW
YXZ, or ZXY
WXZ, or ZXW
You should not name any of these angles X because all three angles have X as their vertex.

18. Degrees: Measuring Angles Angles are measured in units called DEGREES and classified according to their measures.

19. Acute Angles an angle measuring between 0 and 90 degrees

20. Obtuse Angles an angle measuring between 90 and 180 degrees

21. Right Angles an angle measuring exactly 90 degrees.

22. Obtuse Angles an angle measuring between 90 and 180 degrees

23. Degrees: Measuring Angles We measure the size of an angle using a device called the PROTRACTOR.

25. HOW TO USE A PROTRACTOR

26. Place the center point of the protractor on the vertex of the angle.

27. Line up the mark labeled 0 on either scale with one side of the angle.

28. Read the scale where it falls on the other side of the angle.

29. Use a protractor for exercises 1-2
Construct an angle with a measure of 45 degrees.
Construct an angle with measure of 125 degrees.

30. QUIZ 1. NAME THE ANGLES USING 3 POINTS. 2. WHAT ARE THE SIDES OF PAR?
3. WHAT IS THE VERTEX OF DAR? D P A R

31. WHAT ARE THE TYPES OF POLYGON?
HOMEWORK
WHAT IS A POLYGON?
WHAT ARE THE TYPES OF POLYGON?