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\ 06-Nov-2024 Bharat Arora Proof-8 Reader’s Sign _______________________ Date __________
3. Draw a 4 × 4 dot grid in your notbook and make some beautiful Kolam designs and decorate them.
An example is shown below.
(a) (b) (c)
A Pinch of History
Kolam is a floor drawing activity used for centuries in India. The tradition of painting Kolam is
believed to have originated around 5000 years ago. The hisotry of Rangoli can be traced back
to the Indus Valley civilization. Both are basically creative paintings on a natural surface. In
Bhimbetka, the paintings on rocks are around 15,000 years old. One of the 64 arts mentioned
in ancient India is i.e., tandula (rice), kusumavali (array of flowers), vikara
(transformation). Every state has its own form of Kolam. In Andhra Pradesh, it is called
Muggulu, Alpana in West Bengal, Puvidal in Kerala, Chowkpurna in Madhya Pradesh, Mandana
in Rajasthan, Kolam in Tamil Nadu, Sanjhi in Uttar Pradesh etc.
Tile Pattern or Tessellation
Tessellation or tiling is the covering of a plane surface using geometrical shapes with no overlapping
and no gaps between two consecutive tiles. In tessellation patterns, generally, polygons are used
repeatedly to make a beautiful pattern of tiles without leaving any gaps in between.
The interior and exterior angle of any polygon form a straight line, so their angle measure is 180°.
In a regular pentagon, the interior angle is 108°, while the exterior angle is 72°. Note
360°
that the exterior angle of a regular polygon = .
Number of sides 108° 72°
Look at the interior angles of some regular polygons.
Number of sides 3 4 6 8 9 10
Interior angle in
degrees 60° 90° 120° 135° 140° 144°
Observe the tilling patterns given below.
Triangle Pattern Square Pattern Hexagon Pattern
In regular tile patterns only three shapes i.e., equilateral triangles, squares and regular hexagons
can be duplicated infinitely to fill a plane without gaps.
269 Symmetry
