Line segment
A part of a straight line is called a line segment.
Actually, the meaning of line segment is derived from two words “Line” and “Segment”.
- The meaning of Line is a straight path.
- The meaning of segment is a part.
A line segment is graphically represented by a line with two endpoints. It is also known as a line between two points.
Representation
- Graphically, a line segment is represented by a line with two endpoints.
- A line segment is written in mathematics on the basis of graphical representation. So, write names of points one after one and display a line over both points.
Formation
A line segment is formed geometrically in two different ways.
Part of Straight Line
A line segment is basically an extracted part from a straight line.
$\overleftrightarrow{EF}$ is a straight line in a plane and identify any two points ($P$ and $Q$) on the line. Then, extract the small line at points $P$ and $Q$ from the straight line.
The small line which contains $P$ and $Q$ as endpoints, is a part of the straight line $\overleftrightarrow{EF}$. Therefore, it is called as a line segment geometrically.
On the basis of graphical representation of a line segment, the line segment in this example is written as $\overline{PQ}$ and its length is written as $PQ$ in mathematics.
Line between Points
A line that joins any two points in a plane is considered as a line segment. There are two main reasons for this consideration.
- The small line contains two endpoints.
- The distance between two endpoints can be measured and it is equal to the length of the small line.
$M$ and $N$ are two points in a plane and join them by a line. The distance between the two points is equal to the length of the line. Moreover, it seems a line segment. Therefore, a line that joins any two points in a plane can be considered as a line segment.
The line segment is written as $\overline{MN}$ in mathematics and its length is represented by $MN$.