lines

A line is a group of points on a straight path that extends to infinity.

Any two points on the line can be used to name it. This line is called line DE.

A line segment is a part of a line that has two end points.

The two end points of the line segment are used to name the line segment. This line segment is called segment XY.
A ray is part of a line. It has one end point and extends to infinity in one direction. A ray is named starting with its end point first and then any other point on the ray second.

 

Using the graphic to the left:
Name a line:

Name a line segment with
U as an end point:

Name a ray with V
as an end point:


the lines
angles
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