Symmetry
[syn- together + metron measure]
Reflection Symmetry
The simplest symmetry is Reflection Symmetry (sometimes called Line Symmetry or Mirror Symmetry). It is easy to recognise, because one half is the reflection of the other half.
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Here my dog "Flame" has her face made perfectly symmetrical with a bit of photo magic.
The white line down the center is the Line of Symmetry
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The reflection in this lake also has symmetry, but in this case:
- the Line of Symmetry is the horizon
- it is not perfect symmetry, because the image is changed a little by the lake surface.
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The Line of Symmetry does not have to be up-down or left-right, it can be in any direction. To learn more, go to Reflection Symmetry.
Rotational Symmetry
With Rotational Symmetry, the image is rotated (around a central point) so that it appears 2 or more times. How many times it appears is called the Order.
Here are some examples (they were made using Symmetry Artist, and you can try it yourself!)
| Order |
Example Shape |
Artwork |
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| ... and there is Order 4, 5, etc ... |
Point Symmetry
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Point Symmetry is when every part has a matching part:
- the same distance from the orgin
- but in in the opposite direction.
(Note: this is the same as "Rotational Symmetry of Order 2" above)
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