Page 113 - ICSE Math 4

3. Draw and label line segments of the given lengths in your notebook.
(a) 2.5 cm (b) 6 cm (c) 8.5 cm (d) 4.5 cm (e) 3 cm (f) 9.5 cm

Types of Lines

Besides being categorized as straight and curved, lines can be of various other types. Let’s

study about them.
Intersecting Lines Point of intersec on

When two or more lines cross each other at a common
A
point, they are called intersec ng lines. The common A C
O
point where they meet is called the point of intersec on. C O D D B
In the given fi gures, AB and CD intersect at point O. B

Perpendicular Lines

Two lines are said to be perpendicular if they
meet or intersect each other at a point where one
line is drawn completely horizontal to a ver cally
drawn line. plus sign le er T le er L
The symbol for perpendicular is . E G
Some examples of perpendicular lines are given
alongside.
A B
In the given fi gure, EF is perpendicular to AB or
EF  AB and GH is perpendicular to both AB and CD, F
C D
i.e., GH  AB and GH  CD.

H

If the two lines drawn are even slightly lted as shown in
the fi gures given alongside, they are not perpendicular.

Parallel Lines

We all must have seen railway tracks. The two lines of the track never meet each other. So,
we say that the tracks run parallel to each other.

We defi ne parallel lines as those lines which never meet
each other at a point. They are at a equal distance from
each other. The symbol for parallel lines is .

Look at the fi gures given below. In all the fi gure, AB is
parallel to CD or AB CD. Parallel lines may be ver cal,
horizontal or slan ng. Rays and line segments can also be
parallel to each other.

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