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\\October 8, 2025 12:37 PM Bharat Arora P-9 Reader _________________________ Date: ___________________74

one Line of Symmetry reflection Symmetry

Some figures have one line of symmetry. Look at the following figures. If there exists at least one line that divides an object into two halves such that one half is
the mirror image of the other half (one half is reflective of the other half) then the object
A has reflection symmetry.

This symmetry is also known as line symmetry or mirror symmetry. The line of symmetry
can be in any direction: horizontal, vertical, or slanting.

Isosceles triangle Semicircle Arrow Alphabet
more than one Line of Symmetry

Some figures have more than one line of symmetry. Observe the following figures which
have more than one line of symmetry.

activity
Take a piece of paper and fold it in half in any direction, i.e., horizontally Experiential Learning
or vertically. Spill a few drops of ink on half of the paper.

Now, fold the paper along the crease made by folding the paper earlier
and press the halves together.
A circle has an infinite number of lines of symmetry. Unfold the paper and find two identical parts of an image formed by
splitting the ink drops on both sides of the crease. We can clearly see
that the figure formed is symmetrical.

Think Tank Logical Thinking The crease or the fold line is the line of symmetry.
Imagine a square. It has 4 lines of symmetry. If you cut the square in half along its
diagonal, you get a triangle. How many lines of symmetry does this new triangle have?
Practice time 7A
mirror image 1. Fill in the blanks.

When we see an object in the mirror, we see its reflection. ( a) An isosceles triangle has ________ line of symmetry.
A reflection of an object means to produce its mirror image. Right Left ( b) A rectangle has ________ lines of symmetry.

The mirror line is the line of symmetry between the object and ( c) An equilateral triangle has ________ lines of symmetry.
its mirror image (reflection). The mirror image of a figure or an ( d) A circle has ________ lines of symmetry.
object is the same but it appears reversed. ( e) A letter 'H' has ________ lines of symmetry.

The mirror image or reflection of a figure can be made using squared paper. 2. draw the line(s) of symmetry for the following shapes.

If you put a mirror on the line of symmetry, you can get the other half of a ( a) ( b) ( c)
symmetrical figure (see adjoining figure).

activity FACTS
Experiential Learning
Collect leaves or flowers and fold them Symmetry helps butterflies fly ( d) ( e) ( f)
along their line of symmetry. Compare the halves. straight, allows flowers to attract
pollinators, and is found in snowflakes,
Draw or trace the object and its line of symmetry. leaves, and even the human body.

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