CBSE · Class 6-12

Class 6 · Ganita Prakash

Unit 9 · Class 6Ganita Prakash

Symmetry

Line and rotational symmetry in shapes and patterns.

Lessons

4 concepts

1
Line Symmetry
Fold along a line — if halves coincide, shape has line symmetry. A, M, T are symmetric; F, G, J are not.
2
Axes in Polygons
Isosceles triangle: 1 axis. Equilateral: 3. Square: 4. Regular $n$ -gon: $n$ axes.
3
Rotational Symmetry
Rotate about centre. Matches within one full turn → rotational symmetry. Angle between matches $=360°/n$ .
4
Combined Symmetry
Square: 4 lines + rotational order 4. Parallelogram: no line symmetry but rotational order 2.

Skills to practise

Skill · medium

Symmetry — Practice