1. Points, Lines and Planes
Section 1-2
Points, Lines and Planes

2. A Point A point has no dimension.
No length, no width and no thickness.
It is named using capital printed letters.

3. A Line Two points determine a line.B A
Two points determine a line.
A line is an infinite set of points that extends in two directions without ending.
Has no width and no thickness
It is named using a single lower case cursive letter or by two points on the
line,

4. Collinear Noncollinear Points that are on the same line.
Points that ARE NOT on the same line.

5. A Plane At least three noncollinear points determine a plane.B C M
At least three noncollinear points determine a plane.
A plane is an infinite amount of points that creates a flat surface
It extends in two dimensions without ending.

6. A Plane Has no thicknessB C M
Has no thickness
Usually pictured as a parallelogram, although it has NO edges
It is named using a capital cursive letter or by three points in the plane

7. Coplanar Noncoplanar Points that DO NOT lie in the same plane
Points that lie in the same plane
Noncoplanar
Points that DO NOT lie in the same plane

8. A Line segment Piece of a line Has two endpointsX Z
Piece of a line
Has two endpoints
It is named using the two endpoints,

9. ray X Z
Part of a line
Extends indefinitely in one direction. It has exactly one endpoint.
It is named using the endpoint first,

10. Opposite rays Formed by three collinear points Share the same endpointX Z Y
Formed by three collinear points
Share the same endpoint
For example, Y is between X and Z so and are opposite rays

11. Two or more geometric figures intersect if they have one or more points in common.

12. The intersection of two lines is a point.
The intersection of two planes is a line.