Symmetry Two Types: 1. Line Symmetry (can be called reflectional symmetry)– if you can fold a...
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Symmetry Symmetry Two Types: Two Types: 1. Line Symmetry 1. Line Symmetry (can be called (can be called reflectional reflectional symmetry symmetry )– )– if you if you can fold a shape can fold a shape and have the edges and have the edges meet meet The place where you The place where you fold is called the fold is called the line of symmetry line of symmetry
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Transcript of Symmetry Two Types: 1. Line Symmetry (can be called reflectional symmetry)– if you can fold a...
SymmetrySymmetry
Two Types:Two Types:1. Line Symmetry (can 1. Line Symmetry (can
be called be called reflectional reflectional symmetrysymmetry)–)– if you if you can fold a shape and can fold a shape and have the edges meethave the edges meet
The place where you The place where you fold is called the fold is called the line line of symmetryof symmetry
More Line SymmetryMore Line Symmetryreflectional symmetryreflectional symmetry
Line Symmetry in the AlphabetLine Symmetry in the Alphabet
Which letters have got lines of symmetry?Which letters have got lines of 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 lines of symmetry.Click to see the lines of symmetry.
Lines of Symmetry all around usLines of Symmetry all around us
Which of these road signs have got lines of symmetry?Which of these road signs have got lines of symmetry?
Click to see the lines of symmetry.Click to see the lines of symmetry.
CarpetsCarpets
Examples:Examples:
Do the following shapes have line Do the following shapes have line symmetry? If so, how many lines of symmetry? If so, how many lines of symmetry do they have?symmetry do they have?
a. b. c. d. e. a. b. c. d. e.
1 Line1 Line 2 Lines2 Lines 4 Lines4 Lines 2 Lines2 LinesNo No LinesLines
Rotational SymmetryRotational Symmetry
2. Rotational Symmetry: If you can turn 2. Rotational Symmetry: If you can turn the shape less than 360the shape less than 360oo and still have and still have the same shape.the same shape. Order of Rotational Symmetry: Is the Order of Rotational Symmetry: Is the
number of rotations that must be made to number of rotations that must be made to return to the original orientationreturn to the original orientation
Minimum Rotational Symmetry: The Minimum Rotational Symmetry: The smallest number of degrees a shape can smallest number of degrees a shape can be rotated and fit exactly on itselfbe rotated and fit exactly on itself Hint: Take 360Hint: Take 360oo divided by the number of divided by the number of
sides/points.sides/points.
Optional – extra information
SymmetrySymmetry
A figure that has A figure that has rotational symmetryrotational symmetry is its is its own image for some rotation of 180own image for some rotation of 180° ° or or lessless. A figure that has . A figure that has point symmetrypoint symmetry has has 180180° rotational symmetry.° rotational symmetry.
A square has 90° and 180° rotational A square has 90° and 180° rotational symmetry with the center of rotation at the symmetry with the center of rotation at the center of the square. A square also has center of the square. A square also has point symmetry.point symmetry.
Identifying Rotational SymmetryIdentifying Rotational Symmetry
Identify any rotational symmetry in the Identify any rotational symmetry in the figure.figure.
Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has rotational symmetry, It will This figure has rotational symmetry, It will coincide with itself after being rotated 90coincide with itself after being rotated 90° ° or 180° in either direction.or 180° in either direction.
Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has rotational symmetry. It will This figure has rotational symmetry. It will coincide with itself after being rotated 60coincide with itself after being rotated 60°°, , 120120°°, or 180, or 180°° in either direction. in either direction.
Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has no rotational symmetry. It This figure has no rotational symmetry. It does have horizontal line of symmetry.does have horizontal line of symmetry.
Examples:Examples:
Rotational Symmetry all around Rotational Symmetry all around usus
Which road signs have got rotational symmetry?Which road signs have got rotational symmetry?Click to see the answers.Click to see the answers.
Rotational Symmetry all around Rotational Symmetry all around usus
Which road signs have got rotational symmetry?Which road signs have got rotational symmetry?
Rotational Symmetry all around Rotational Symmetry all around usus
Click to see the road signs with rotational symmetry.Click to see the road signs with rotational symmetry.
Order 3 Order 2 Order 2
Rotational Symmetry all around Rotational Symmetry all around usus
Click to see more road signs with rotational symmetry.Click to see more road signs with rotational symmetry.
Order 4 Order 3 Order 2
Rotational Symmetry all around Rotational Symmetry all around usus
Click to see more road signs with rotational symmetry.Click to see more road signs with rotational symmetry.
Order 3 Order 2
