The line of symmetry is the axis or imaginary line that passes through the center of the shape or object and divides it into identical halves.

Table of Contents

## How to find a shape has a Line of Symmetry ?

- You can find a shape has a Line of Symmetry or not by folding it
- When the folded part sits perfectly on top (all edges matching), then the fold line is a Line of Symmetry.

### Examples

Plane Shape | Folding it | |

The folding Line is Line of Symmetry | ||

The folding Line is NOT Line of Symmetry |

## Triangle

A Triangle can has 3, or 1 or no lines of symmetry:

Equilateral Triangle(all sides equal, all angles equal) | 3 Lines of Symmetry |

Isosceles Triangle(2 sides equal, 2 angles equal) | 1 Line of Symmetry |

Scalene Triangle(no sides equal, no angles equal) | no Line of Symmetry |

## Quadrilaterals

A Quadrilateral 4, 2, or 1 or no lines of symmetry:

Square(all sides equal, all angles 90°) | 4 Lines of Symmetry |

Rectangle(opposite sides equal, all angles 90°) | 2 Lines of Symmetry |

Rhombus(all sides equal length) | 2 Lines of Symmetry |

Kite | 1 Line of Symmetry |

Irregular Quadrilateral | no Line of Symmetry |

## Regular Polygons

3 Sides | Equilateral Triangle | 3 Lines of Symmetry |

4 Sides | Square | 4 Lines of Symmetry |

5 Sides | Regular Pentagon | 5 Lines of Symmetry |

6 Sides | Regular Hexagon | 6 Lines of Symmetry |

7 Sides | Regular Heptagon | 7 Lines of Symmetry |

8 Sides | Regular Octagon | 8 Lines of Symmetry |

And the pattern continues:

A regular polygon with 9 sides has 9 Lines of Symmetry

A regular polygon with 10 sides has 10 Lines of Symmetry

…

A regular polygon with “n” sides has “n” Lines of Symmetry

## Circle

Any line that goes through its center is a Line of Symmetry.

So a Circle has infinite Lines of Symmetry.