Here my dog "Flame" has her face made perfectly symmetrical with a bitof photograph magic.

The white line under the center is present of Symmetry


When the folded component sits perfect on peak (all edges matching), climate the fold line is a heat of Symmetry.


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

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So this is not a heat of Symmetry

But as soon as 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 political parties equal, 2 angles equal) Scalene Triangle(no sides equal, no angles equal)
3 present of Symmetry1 heat of SymmetryNo lines of Symmetry

Quadrilaterals

Different varieties of square (a 4-sided airplane shape):

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Square(all political parties equal, all angle 90°) Rectangle(opposite sides equal, all angles 90°)Irregular Quadrilateral
4 currently of Symmetry2 currently of SymmetryNo currently of Symmetry

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KiteRhombus(all sides same length)
1 heat of Symmetry2 currently of Symmetry

Regular Polygons

A continual polygon has actually all sides equal, and all angles equal:

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

And the pattern continues:

A continual polygon of 9 sides has actually 9 currently of SymmetryA consistent polygon of 10 sides has 10 lines of Symmetry...A consistent polygon the "n" sides has actually "n" present of Symmetry

Circle