Here mine dog "Flame" has her face made perfectly symmetrical through a bitof picture magic.

The white line down the facility is theline of Symmetry


When the folded part sits perfect on peak (all edge matching), then the wrinkles line is a line of Symmetry.


Here I have folded a rectangle one way, and it didn"t work.

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So this is not a heat of Symmetry

But once I try it this way, the does work (the folded component sits perfect on top, every edges matching):

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So this is a heat of Symmetry

Triangles

A Triangle have the right to have 3, or 1 or no present of symmetry:

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Equilateral Triangle(all sides equal, all angle equal) Isosceles Triangle(two sides equal, 2 angles equal) Scalene Triangle(no political parties equal, no angle equal)
3 currently of Symmetry1 line of SymmetryNo currently of Symmetry

Quadrilaterals

Different species of quadrilateral (a 4-sided aircraft shape):

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Square(all sides equal, all angles 90°) Rectangle(opposite sides equal, all angles 90°)Irregular Quadrilateral
4 present of Symmetry2 lines of SymmetryNo lines of Symmetry

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KiteRhombus(all sides same length)
1 line of Symmetry2 lines of Symmetry

Regular Polygons

A continuous polygon has actually all political parties equal, and all angles equal:

An Equilateral Triangle (3 sides) has 3 lines of Symmetry
A Square (4 sides) has 4 present of Symmetry
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A Regular Pentagon (5 sides) has 5 lines of Symmetry
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A Regular Hexagon (6 sides) has 6 lines of Symmetry
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A Regular Heptagon (7 sides) has 7 present of Symmetry
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A Regular Octagon (8 sides) has 8 currently of Symmetry

And the pattern continues:

A consistent polygon the 9 sides has 9 lines of SymmetryA consistent polygon that 10 sides has 10 lines of Symmetry...A constant polygon that "n" sides has "n" present of Symmetry

Circle