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Maths Exercices

Symmetry

There are two types of symmetry that you should know:

Reflectional Symmetry
Rotational Symmetry
  • A figure has reflectional symmetry or symmetry about a line if reflection across the line produces an identical figure.
  • A figure has rotational symmetry or symmetry about a point P is a rotation of k degrees, 0<k<360, clockwise or counterclockwise, about P produces an identical figure.
Note that the figure on the left does not have symmetry about a point, and the figure on the right does not have symmetry about a line. Many of figures, however, have both types of symmetry.

A figure has reflectional symmetry or symmetry about a line if a line can be drawn through it, dividing it into two parts that are the same but facing in opposite directions.


Is the dotted line a line of symmetry?



Yes
No