Page 246 - Start Up Mathematics_6

5. Complete the following figures such that the dotted line becomes the line of symmetry.

(a) (b) (c)

(d) (e) (f)

Figures with more than one line of symmetry

We have already dealt with figures having more than one line of symmetry. Let’s consider
some more cases. What do you observe?

l 1 l l
2 1
l l 1 l
l 2 2
3 l
l 1
l 3
4
l 3
l l
l 4 2
5
l l l
6 5 4

MATHS LAB ACTIVITY

1. Finding line(s) of symmetry of a circle
Step 1: Draw a circle on a white sheet of
paper.
Step 2: Cut this circle using a pair of
scissors.
Step 3: Fold the circle in such a way that
the crease passes through the centre
of the circle.
Step 4: We observe that each half part of the circle overlaps the other completely.
Therefore, on unfolding the crease so formed we get a line of symmetry.
Step 5: Now, keep folding the circle again and again along different lines.
Step 6: Everytime we obtain a new line of symmetry passing through the
centre.
Step 7: Therefore, it is clear that a circle has infinite lines of symmetry.

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