 # © T Madas. A shape has rotational symmetry, if it looks the same in more than one position, when rotated about its centre. We say it has a rotational.

## Presentation on theme: "© T Madas. A shape has rotational symmetry, if it looks the same in more than one position, when rotated about its centre. We say it has a rotational."— Presentation transcript:

A shape has rotational symmetry, if it looks the same in more than one position, when rotated about its centre. We say it has a rotational symmetry of order 2 if it looks the same in 2 positions within a whole turn

A shape has rotational symmetry, if it looks the same in more than one position, when rotated about its centre. We say it has a rotational symmetry of order 3 if it looks the same in 3 positions within a whole turn

© T Madas A shape has rotational symmetry, if it looks the same in more than one position, when rotated about its centre. We say it has a rotational symmetry of order 4 if it looks the same in 4 positions within a whole turn

© T Madas R o t a t i o n a l S y m m e t r y P r a c t i c e

© T Madas Find the order of rotational symmetry for each shape: 4 6 32

© T Madas Find the order of rotational symmetry for each shape: 6 3 none

We we start we the flag shape below We want to create a new shape with rotational symmetry We pick a point as the centre of rotation For rotational symmetry of order 2: We rotate the shape by 180° 180° 360 ÷ 2 = 180

© T Madas For rotational symmetry of order 4: We rotate the shape by 90° 90° 360 ÷ 4 = 90

© T Madas For rotational symmetry of order 3: We rotate the shape by 120° 120° 360 ÷ 3 = 120

© T Madas For rotational symmetry of order 5: We rotate the shape by 72° 72° 360 ÷ 5 = 72

© T Madas R o t a t i o n a l S y m m e t r y P r a c t i c e

Shade one or more squares to create a shape with rotational order: 2

© T Madas R o t a t i o n a l S y m m e t r y P r a c t i c e

© T Madas Make a shape with rotational symmetry of order 2

© T Madas Make a shape with rotational symmetry of order 4

© T Madas Make a shape with rotational symmetry of order 3

© T Madas R o t a t i o n a l S y m m e t r y P r a c t i c e

Shade this shape so that it has rotational symmetry of order 4

Complete each shape so it has rotational symmetry of order 2 about the given point. 1 2 3 4 6 5

1 4 6 5 Complete each shape so it has rotational symmetry of order 4 about the given point. 2 3

Shade some of the squares in the following two grids so that the resulting pattern has order of rotational symmetry of 4.

Part of a shape is drawn on this grid. The shape has rotational symmetry of order 4, about the point P. Complete the shape. P

a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 1 2 3 4

© T Madas a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 1 2 3 4

© T Madas 1 a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 2 3 4 Order 3

© T Madas 1 a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 2 3 4 Order 3 Order 2

© T Madas 1 a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 2 3 4 Order 3 Order 2 Order 1

© T Madas 1 a)Mark all the lines of symmetry on each shape. b)For the shapes that have rotational symmetry, write down its order. 2 3 4 Order 3 Order 1 Order 2

Look at the shapes labelled as A to F 1.Write the letter of the shapes that have 2 lines of symmetry. 2.Write the letter of the shapes that have rotational symmetry of order 2. ABC D E F

© T Madas Look at the shapes labelled as A to F 1.Write the letter of the shapes that have 2 lines of symmetry. 2.Write the letter of the shapes that have rotational symmetry of order 2. ABC D E F

ACB Four road signs are shown below. 1.Write down the letter of the two signs that have one line of symmetry. 2.Write down the letter of the sign that has rotational symmetry and state the order of this symmetry. D

© T Madas AB Four road signs are shown below. 1.Write down the letter of the two signs that have one line of symmetry. 2.Write down the letter of the sign that has rotational symmetry and state the order of this symmetry. CD Order 3