This post is also available in: हिन्दी (Hindi)

A line segment is a straight line with two endpoints. A line segment has a fixed length and can be measured using a ruler. Constructing a line segment is the basic construction in Geometry.

Let’s understand how to construct a line segment with steps and examples.

## How to Construct a Line Segment of Given Length

Suppose we want to construct a line segment of length $4.3$ cm using ruler. We can use our ruler and mark two points $\text{A}$ and $\text{B}$ which are $4.3$ cm apart. Join $\text{A}$ and $\text{B}$ and get $\text{AB}$. While marking points $\text{A}$ and $\text{B}$, we should look straight down at the measuring device. Otherwise, we will get an incorrect value.

### Steps to Construct a Line Segment of Given Length

These are the steps to construct a line segment of length $4.3$ cm using ruler.

**Step 1:** Draw a line $l$. Mark a point $\text{A}$ on a line $l$.

**Step 2:** Place the compass pointer on the zero mark of the ruler. Open it to place the pencil point up to the $4.3$ cm mark.

**Step 3: **Taking caution that the opening of the compasses has not changed, place the pointer on $\text{A}$ and swing an arc to cut $l$ at $\text{B}$.

**Step 4:** $overline{\text{AB}}$ is a line segment of a required length.

## How to Construct a Copy of a Given Line Segment

After understanding how to construct a line segment, let’s understand how to construct a copy of a given line segment. Suppose you want to draw a line segment whose length is equal to that of a given line segment $\overline{\text{AB}}$ using a ruler and a compass.

### Steps to Construct a Copy of a Given Line Segment

These are the steps to construct a copy of a given line segment.

**Step 1:** Given $\overline{\text{AB}}$ whose length is not known.

**Step 2:** Fix the compass pointer on $\text{A}$ and the pencil end on $\text{B}$. The opening of the instrument now gives the length of $\text{AB}$.

**Step 3: **Draw any line $l$. Choose a point $\text{C}$ on $l$. Without changing the compass’s setting, place the pointer on $\text{C}$.

**Step 4:** Swing an arc that cuts $l$ at a point $\text{D}$. Now $\text{CD}$ is a copy of $\text{AB}$.

## Practice Problems

- Construct a line segment of length
- $2.8$ cm
- $5.4$ cm
- $7.2$ cm

- Construct a copy of the above line segments.

## FAQs

### Which tool is used to construct a line segment?

A ruler and Compass are used to draw a line segment.

### What are constructions in maths?

Constructions are accurate drawings of shapes, angles, and lines in geometry. To do this we need to use a pencil, a ruler, and compasses.

## Conclusion

A line segment is a part of a line of fixed length. We can construct a line segment using a ruler and a compass and the same instruments are used to copy a given line segment.

## Recommended Reading

- What are Collinear Points in Geometry – Definition, Properties & Examples
- What is a Transversal Line in Geometry – Definition, Properties & Examples
- What are Parallel Lines in Geometry – Definition, Properties & Examples
- What is Concurrent lines in Geometry – Definition, Conditions & Examples
- What is Half Line in Geometry – Definition, Properties & Examples
- What is a Perpendicular Line in Geometry – Definition, Properties & Examples
- Difference Between Axiom, Postulate and Theorem
- Lines in Geometry(Definition, Types & Examples)
- What Are 2D Shapes – Names, Definitions & Properties
- 3D Shapes – Definition, Properties & Types