1.1 Points Lines And Planes

Question: Point

Answer: An exact position or location, has no size, and is represented by a dot. (It is named by a capital letter).

Question: Line

Answer: A straight path that has no thickness and extends forever. It consists of an infinite number of points. (It is named by a single lowercase letter or any two points on the line.)

Question: Plane

Answer: A flat, infinite surface that has no thickness and extends forever. It’s defined by three different points that do not lay on the same line. (It’s named by a single capital letter or by three points not on a line.)

Question: Segment

Answer: Is a part of a line consisting of two points called endpoints and all points between them. (It is named by its endpoints with a line above them without arrows! The order of the points is not important.)

Question: Ray

Answer: Is a part of a line that starts at an endpoint and extends forever in one direction. It is named by its endpoint and any other point on the ray. (The endpoint must be named first no matter the direction it points!)

Question: Opposite Rays

Answer: These are two rays that have a common endpoint and form a line (they must go in opposite directions).

Question: Coplanar

Answer: Points/lines that lie on the same plane are coplanar. Noncoplanar are points that do not line on the same plane. *Any 3 points are always coplanar.

Question: Collinear

Answer: Points that lie on the same line are collinear. Noncollinear are points that do not line on the same line. *Any 2 points are always collinear.

Question: Point (Diagram)

Answer:

Question: Line (Diagram)

Answer: