Points, Lines, and Planes
Points
A point has no dimensions. It is represented by a small
dot.
Naming Points
Points are named by one letter.
Examples:
Point A or
Lines
A line has one dimension. It extends without end in two
directions.
Naming Lines
Lines are named by two points with arrowheads heading
in each direction or by a cursive letter.
Examples:
Segments
A segment is similar to a line but does continue in both
directions. A segment ends at two endpoints.
Naming Segments
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Like lines, segments are named by two points but with
no arrows at the ends above the two points.
Example:
Rays
A Ray is a combination of a line and a segment. At one
end of a ray there is a endpoint and the other end
continues in that direction.
Naming Rays
Rays are named by two points in the direction of travel.
Above the two points there is an endpoint and one
arrow.
Examples:
Planes
A plane has two dimensions. A plane looks like a floor or
a wall and continues on without end.
Naming Planes
Planes are named by three points or by a letter in the
corner of the plane.
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corner of the plane.
Collinear Points
-Points that lie on the same line
Examples:
Coplaner Points
-Are points that lie in the same plane
Examples:
Coplaner Lines
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Coplaner Lines
-Are lines that lie on the same plane
Examples:
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