Page 190 - Maths Class 06

Linear Symmetry
A figure is said to have linear symmetry if there exists a line that can be drawn such that figure drawn on
the one side of the line coincides with the image on the other side of the line. It is also re ferred to as a
FLIP, lat eral sym me try or mir ror im age sym me try.
Axis of Symmetry : The line or fold at which the two halves coincide each other is called the axis of
sym me try. A fig ure may have more than one axis of sym me try.
For example, a circle can be folded along any of its diameter to get two semicircles which are
symmetrical. Hence, a circle has infinite lines of symmetry whereas a parallelogram has no line of
symmetry.

Fig. 13.5 Fig. 13.6

Take coloured sheets of paper and cut a square, rectangle, an isosceles triangle, a scalene triangle, an
equilateral triangle, a circle, and a pentagon.

(a) (b) (c) (d) (e)
Fig. 13.7
Now, fold each of them to find the number of lines of symmetry and record your observation in the
adjacent table:

S.No. Geometrical Shape Figure Number of Lines of Symmetry

1. Square

2. Rectangle

3. Isosceles triangle

4. Equilateral triangle

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