• A figure has a line of symmetry, if it can be divided into two equal parts.
  • In the above figure the line AB divides this hexagon into two equal parts.
  • The figure may have no line of symmetry, one line of symmetry, two or more lines of symmetry.
  • The rectangle has four lines of symmetry.  These lines are AB, CD, EF, GH.
  • The scalene triangle has no line of symmetry, as its all its three sides are of unequal length.
  • The equilateral triangle has two lines of symmetry.
  • The isosceles triangle has one line of symmetry.
  • The circle has infinite lines of symmetry. 
  • The and rectangle are symmetrical about its diagonals.
  • The rhombus is symmetrical about perpendicular bisector of its sides.
  • The letters which have one line of symmetry are A, B, C, D, E, K, M, T, U, V, Y
  • The letters which have no line of symmetry are R, F, L, P etc
  • The letters which have two lines of symmetry are H, I, X
  • The letter which has infinite lines of symmetry is O.
  • Some symmetrical figures are 
  • The symmetry is used in various fields, such as art and architecture, creating designs of rangoli, textile, technology etc.

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