1. SymmetrySymmetry
Two Types:Two Types:
1. Line Symmetry (can1. Line Symmetry (can
be calledbe called reflectionalreflectional
symmetrysymmetry)–)– if youif you
can fold a shape andcan fold a shape and
have the edges meethave the edges meet
The place where youThe place where you
fold is called thefold is called the lineline
of symmetryof symmetry
3. 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.
4. Lines of Symmetry all around usLines of Symmetry all around us
Which of these road signs have got lines ofWhich of these road signs have got lines of
symmetry?symmetry?Click to see the lines of symmetry.Click to see the lines of symmetry.
6. Examples:Examples:
Do the following shapes have lineDo the following shapes have line
symmetry? If so, how many lines ofsymmetry? 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 Lines
NoNo
LinesLines
7. Rotational SymmetryRotational Symmetry
2. Rotational Symmetry: If you can turn2. Rotational Symmetry: If you can turn
the shape less than 360the shape less than 360oo
and still haveand still have
the same shape.the same shape.
Order of Rotational Symmetry: Is theOrder of Rotational Symmetry: Is the
number of rotations that must be made tonumber of rotations that must be made to
return to the original orientationreturn to the original orientation
Minimum Rotational Symmetry: TheMinimum Rotational Symmetry: The
smallest number of degrees a shape cansmallest 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 ofdivided by the number of
sides/points.sides/points.
Optional – extra information
8. SymmetrySymmetry
A figure that hasA figure that has rotational symmetryrotational symmetry is itsis its
own image for some rotation of 180own image for some rotation of 180°° oror
lessless. A figure that has. A figure that has point symmetrypoint symmetry hashas
180180° rotational symmetry.° rotational symmetry.
A square has 90° and 180° rotationalA square has 90° and 180° rotational
symmetry with the center of rotation at thesymmetry with the center of rotation at the
center of the square. A square also hascenter of the square. A square also has
point symmetry.point symmetry.
10. Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has rotational symmetry, It willThis 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.
11. Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has rotational symmetry. It willThis 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.
12. Identifying Rotational SymmetryIdentifying Rotational Symmetry
This figure has no rotational symmetry. ItThis figure has no rotational symmetry. It
does have horizontal line of symmetry.does have horizontal line of symmetry.
14. Rotational Symmetry all aroundRotational 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.
15. Rotational Symmetry all aroundRotational Symmetry all around
usus
Which road signs have got rotational symmetry?Which road signs have got rotational symmetry?
