# How Do You Construct A Line Segment

## Construction Of A Line Segment

### To draw a line segment of a given length

We can draw a line segment of a given length in two ways:
(a) By using a scale
(b) By using a pair of compasses

Construction: Draw a line segment of length 5.5 cm.

(a) By using a scale

• Step 1: Mark a point in your notebook and label it as A.
• Step 2: Place the scale in such a way that the zero (0) mark on the scale coincides with A.
• Step 3: How, move the sharp end of the pencil along the edge of the scale till it reaches the point 5.5 cm of the scale,
• Step 4: Label the second end as B.
AB is the required line segment.

(b) By using a pair of compasses

• Steps 1: Draw a line l and mark a point A on it.
• Step 2: Open the arms of the compass so that the end points of the two open arms equal to 5.5 cm.
• Step 3: Without disturbing the opening of the compasses, place its needle at point A and draw an arc to cut the line l at point B.
• Step 4: AB is the required line segment of length 5.5 cm.

### To draw a line segment equal to a given line segment

Construction: Draw a line segment (AB) equal to PQ.
Given: A line segment PQ.

• Step 1: Draw a line l. Mark a point A on it.
• Step 2: Take the compass and measure PQ.
• Step 3: Without disturbing the opening, place the needle of the compass at point A on line l and draw an arc, which cuts the line at point B.
• Step 4: AB is the required line segment which is equal to the length of PQ, i.e., AB = PQ.

Construction: Draw a line segment whose length is the sum of the lengths of two given line segments.
Given: Two line segments AB and BC.
Construct a line segment, say AC, such that
AC = AB + BC.

• Step 1: Draw a line l and mark point A on it.
• Step 2: Take the compasses and measure AB.
• Step 3: Without disturbing the opening, place its needle at A and draw an arc cutting line l at B.
• Step 4: Again adjust the compasses and measure the line segment BC.
• Step 5: Without disturbing the opening, place the pointer at point B on the line l and draw an arc cutting the line l at C.
• Step 6: AC is the required line segment whose length is equal to the sum of the lengths of line segments AB and BC, i. e., AC = AB + BC.