A Line Segment

Imagine you mark two points, A and B, on a sheet of paper. If you connect these points with a straight line, the portion between them is called a line segment.

It is written as AB with a small line above it.

A line segment has a fixed length, meaning the distance between A and B can be measured accurately. Unlike a line, which extends infinitely, a line segment has two definite endpoints.

Below, select any two random points and join the points to make a line segment.

We can draw a line segment of a specific length using two methods:

Method 1

1. Using a Ruler

Example: Suppose we need to draw a line segment of 7.8 cm.

Steps:

1. Place a ruler flat on the paper and hold it steady.

2. Use a sharp pencil to mark a point at the 0 cm mark. Label this point as A.

3. Find the cm mark on the ruler and make another point there. Label it as B.

4. Using the ruler’s edge, draw a straight line connecting A and B.

5. The segment AB is the required line segment of 7.8 cm.

2. Using a Compass

Example: Suppose we need to construct a line segment of 5.3 cm.

Steps:

1. Draw a Base Line: Start by drawing a straight line l on the paper. Mark a point A on it.

2. Set the Compass:

• Place the metal pointer of the compass at the 0 cm mark on a ruler.

• Open the compass until the pencil tip reaches the 5.3 cm mark.

3. Mark the Second Point:

• Position the compass pointer on A.

• Without changing the compass width, draw an arc across the line l.

• The point where the arc meets the line is labeled as B.

4. Complete the Segment: The segment AB is the required 5.3 cm line segment.

This method ensures precise measurements and is useful when working without a ruler.