rotational symmetry rotational symmetry if, when you rotate a shape, it looks exactly the same as...

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Rotational Symmetry

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Rotational Symmetry• If, when you rotate a shape, it looks exactly

the same as it did in its original position, then we say that the shape has got rotational symmetry.

• This square has got rotational symmetry.

• It looks exactly the same four times in a full turn.• It has got rotational symmetry order 4.

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Rotational Symmetry• Does this rectangle have rotational symmetry?

• It looks exactly the same twice in a full turn.• It has got rotational symmetry order 2.

Yes, it fits!No, it doesn’t fitNo, it doesn’t fitYes, it fits!

Click to rotate the rectangle.

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Rotational Symmetry in the Alphabet

Which letters have got rotational symmetry?

A B C D E F G H I

J K L M N O P Q R

S T U V W X Y Z

Click to see the answers.

Order 2 Order 2 Order 2

Order 2 Order 2 Order 2

Order 2

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Rotational Symmetry all around usWhich road signs have got rotational symmetry?

Click to see the answers.

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Rotational Symmetry all around usClick to see the road signs with rotational symmetry.

Order 3 Order 2 Order 2

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Rotational Symmetry all around usClick to see more road signs with rotational symmetry.

Order 4 Order 3 Order 2

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Rotational Symmetry all around usClick to see more road signs with rotational symmetry.

Order 3 Order 2

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Rotational Symmetry with Pentominoes

• If you don’t know what a pentomino is, then click here.

• If you have done the pentominoes activity before, then you will know what a pentomino is and how many different pentominoes there are.

• Here they are ...

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Rotational Symmetry with Pentominoes

Which Pentominoes have got rotational symmetry?

Sort them according to their rotational symmetry.

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Rotational Symmetry with Pentominoes

Rotational Symmetry Order 2Rotational Symmetry Order 2 Rotational Symmetry Order 4Rotational Symmetry Order 4

Click to start sorting

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Rotational Symmetry with 7-Pin Polygons

• If you don’t know what a 7-pin polygon is, then click here.

• If you have done the 7-pin polygons activity before, then you will know what a 7-pin polygon is and how many different ones there are.

• Here they are ...

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Rotational Symmetry with 7-Pin Polygons

Which 7-Pin Polygons have got rotational symmetry?Sort them according to their rotational symmetry.

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Rotational Symmetry with 7-Pin PolygonsRotational Symmetry Rotational Symmetry

Order 2Order 2Rotational Symmetry Rotational Symmetry

Order 6Order 6Rotational Symmetry Rotational Symmetry

Order 3Order 3

Click to start sorting

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Now you know all about rotational symmetry!

END OF PRESENTATION

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Pentominoes

A pentomino is made out of five squares that are connected along at least one edge.

These are NOT pentominoes.

Here is an example of a pentomino.

How many different pentominoes can you find?

Click here to return to line symmetry.

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7-Pin PolygonsHere is an arrangement of 7 pins.

Here are some examples of 7-pin polygons.

How many different 7-pin polygons can you find?

Click here to return to line symmetry.

A 7-pin polygon is a closed shape with straight sides with corners on the pins.

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END OF PRESENTATION

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