Identify points, lines, line segments, and rays

Detailed Explanation: Identify points, lines, line segments, and rays

A point shows one exact location. It is drawn as a dot and named with one capital letter, such as $A$.

To identify a geometric object in a drawing:

• Line segment: Look for two endpoint dots with no arrows. It has a beginning and an end. Name it with $\overline{BC}$ or $\overline{CB}$.
• Line: Look for arrows in both directions. It continues forever both ways. Name it with $\overleftrightarrow{DE}$ or $\overleftrightarrow{ED}$.
• Ray: Look for one endpoint dot and one arrow. It begins at the endpoint and continues forever in one direction. Name it with the endpoint letter first.

Consider this drawing:

Point:    A •

Segment:  B •────────• C

Line:     ←────• D────────• E────→

Ray:      F •────────• G────→

Step 1: Find the point

$A$ is a single dot showing one exact location. It is point $A$.

Step 2: Find the line segment

The drawing from $B$ to $C$ has two endpoint dots and no arrows. It is a line segment:

You could also write $\overline{CB}$ because the order does not matter for a segment.

Step 3: Find the line

The drawing through $D$ and $E$ has arrows at both ends, so it continues forever in both directions. It is a line:

You could also write $\overleftrightarrow{ED}$.

Step 4: Find the ray

The drawing starts at the dot $F$ and has an arrow pointing past $G$. It is a ray:

The endpoint must be named first, so $\overrightarrow{GF}$ would name a different ray.