1.2 - Points, Lines, Planes

1.2 - Points, Lines, Planes

by Steve Dull

​Some definitions:

​Point: a geometric object with a location but having no dimensions

​Line: a line is made up of points. It has no beginning or end.

• ​Any two points define a line

• ​A line is named by any two points on the line, or by a lowercase letter

​Collinear points lie on the same line.

​Non-collinear points do not lie on the same line (must be at least three points)

​Plane: a flat surface made up of points. any three points define a plane. It extends infinitely in all directions.

​Name a plane by three non-collinear points

​Two lines intersect at a point. Two planes intersect at a line.

Open Ended

What is something you see in the room that could represent a plane?

Open Ended

What is something in the room that could represent a line?

Multiple Choice

An example of 2 non-collinear points.

• D, E

• C, B

• M, E

• F, B

Multiple Choice

Give another name for line k.

• Line BC

• Line BCE

• Line ED

• Line k is the only name, there isn't another name.

Multiple Choice

Name the intersection of Plane ADE and Plane W

• Point E

• Point A

• Line AD

• Line EA

Multiple Choice

Points that lie on the same line are _________.

• coplanar

• collinear

• parallel

• perpendicular

Multiple Choice

An exact location in space with no length or width is a _____.

• Ray

• Point

• Line

• Line segment

Multiple Choice

A line that extends from a point in one direction and travels forever is called a ...

• perpendicular line

• line segment

• ray

• parallel line

Multiple Choice

What is a line segment?

• Part of a line with 2 endpoints

• Part of a line that has 1 endpoint

• Part of a line with 0 endpoints

• Part of a line with 5 endpoints