1. 1.3 & 1.4 Points, Lines, Segments, & Rays
Objective: To Understand Basic Terms/Postulates of Geometry

2. Point A point refers to location It has no size
A point in represented by a dot and is named by capital letters

3. Line A series of points that extends indefinitely
A line is named by a lower case script letter or any 2 points on the line

4. Collinear Points
Points that lie on the same line

5. Example 1
a) Are points E, F, and C collinear? If so, which line are they on?
b) Are points E, F, and D collinear? If so, which line are they on?
c) Name line l in 3 other ways.

6. Line Segment
The part of a line consisting of two endpoints and all points between them
A line segment is named by its 2 endpoints

7. Ray
The part of a line consisting of one endpoint and all the points of the line on one side of the endpoint
A ray is named by the endpoint and one other point on the ray; must start with the end point

8. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Line Segment

9. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Line

10. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Ray

11. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Line

12. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Ray

13. Identify the type of line: line, ray, or line segment.
Your Turn!
Identify the type of line: line, ray, or line segment.
Line Segment

14. Opposite Rays
Two collinear rays with the same endpoint; they always form a line

15. Example 2 Name ALL line segments.

16. Name the rays.
Are ray LP and ray PL opposite rays?

17. Read: “Line JK is parallel to line LM”
Parallel Lines
Parallel Lines- lines that never cross or become further apart from each other. J K L M
Read: “Line JK is parallel to line LM” ║ JK LM

18. Intersecting Lines- lines that cross each other.Q P OP
intersects QR

19. Read: “Line ST is perpendicular to line UV”
Perpendicular Lines
Perpendicular Lines- lines that cross or meet each other to form square corners (90º angle). U
90º/Right Angle S T
Read: “Line ST is perpendicular to line UV” V ST ┴ UV

20. Your Turn!
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Parallel

21. Your Turn!
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Parallel

22. Your Turn! Intersecting
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Intersecting

23. Your Turn! Perpendicular
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Perpendicular

24. Your Turn!
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Parallel

25. Your Turn! Intersecting
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Intersecting

26. Your Turn! Perpendicular
Identify if the lines are parallel, perpendicular, or intersecting (not at a perpendicular angle).
Perpendicular

27. What is a Postulate?
A postulate or axiom is an accepted statement of fact

28. Postulate 1-1
Through any 2 points there is exactly 1 line

29. Postulate 1-2
If 2 lines intersect, then they intersect in exactly 1 point

30. Think about streets in Lyndhurst…
Name of street that is a line.
Name a street that is a line segment.
Name a street that is a ray.