Eg1. A square

1
Eg1. A square
It fits on itself 4 times
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We say that a square has
2
Eg2. A heart shape
It fits on itself only once
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We say that a heart has
3
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4
Rotational Symmetry

• The order of rotational symmetry of a shape is
  determined by how many times the shape fits onto
  itself during a 360 turn. (Example 1)
• Every shape has an order of rotational symmetry,
  even if it is order 1. (Example 2)
• Have a look at the following shapes

5
What is the order of rotational symmetry?
answer
6
What is the order of rotational symmetry?
answer
7
What is the order of rotational symmetry?
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8
What is the order of rotational symmetry?
answer
9
4
3
2
A
1
0
-4 -3 -2
-1 0 1 2 3
4
-1
-2
-3
-4