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4. Find the lines of symmetry of the following figures with punched holes.

(a) (b) (c) (d)

(e) (f)

5. Given the line(s) of symmetry, find the other hole(s):

(a) (b) (c) (d) (e)

6. Which of the following figures has multiple lines of symmetry?
(a) (b) (c)

7. State the number of lines of symmetry for the following geometrical figures:

(a) Rectangle (b) Isosceles triangle (c) Semicircle (d) Regular decagon
(e) A parallelogram (f) Square

8. Give three examples of shapes with no line of symmetry.

Rotational Symmetry

We are familiar with the rotation in our everyday activities,
such as a ceiling fan rotating about its centre, a door rotating Think and Answer
about an axel, etc. Have you observed the rotation of

Do you observe the hands of a clock? The direction of motion the blades of a ceiling fan?
of the clock’s hands is called clockwise motion. In which direction do they rotate?
(a) clockwise
When an object rotates in the direction of motion of the (b) anticlockwise
hands of a clock, this rotation is called clockwise rotation, (c) rotate both ways
otherwise, it is said to be anti-clockwise rotation.

A rotation is a transformation that rotates all points in a plane about a fixed point through a given
angle in a clockwise or anticlockwise direction.
If a figure is rotated around a centre point and it still appears exactly as it was before the rotation,
it is said to have a rotational symmetry.

The minimum angle through which the figure has to be rotated to get the original shape/position
is called the angle of rotation. And the point about which the figure is rotated, is known as the
centre of rotation.

Let us take a ceiling fan and rotate it around its centre marked as a red cross.

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