Post on 03-Jan-2016
description
SymmetryTRANSFORMATIONS
RotationTranslationReflectionDilation
HOMEWORK: Symmetry WS
Symmetry
What is a line of symmetry?
• A line on which a figure can be folded so that both sides match. To coincide.
To be a line of symmetry, the shape must have two halves that match exactly.
When you trace half a heart onto a piece of folded paper, and then cut it out, the two half hearts make a whole heart. The two halves are symmetrical.
Which of these flags have a line of symmetry?
United States of America Canada
Maryland England
What about these math symbols?Do they have symmetry?
How many lines of symmetry to these regular polygons have?
Do you see a pattern?
Identify the letters that are Horizontally or Vertical Lines of Symmetry
A B C D E FG H I J K L M N O P Q R S T U V W X Y Z
Infinite number
Symmetrical WordsA H I M O T U V W X Y
Vertically Symmetric
B C D E H I K O X
Horizontally Symmetric
Rotational Symmetry(Turn)
The action of turning a figure around a point or a
vertex.
Rotational Symmetry
Rotational Symmetry all around usWhich road signs have got rotational symmetry?
Click to see the answers.Click to see the answers.
Rotational Symmetry all around usWhich road signs have got rotational symmetry?
Identify the Rotationally Symmetric Letters
A B C D E FG H I J K L M N O P Q R S T U V W X Y Z
Maryland
Letters may possess rotational symmetry.
H I N O S X Z
H I N O S X Z
Flags may possess rotational symmetry.
Point Symmetry
A figure also has point symmetry if it can be rotated 180 degrees.
360/4 = 90 two rotation make 180
Examples:Name the type(s) of symmetry each figure has.
Rotation of 120 reflection
Rotation and point
reflection
Click the
triangle to
see rotationTurning a figure around a point or a vertex
Translation (Slide)
The action of sliding a figure in any direction.
The act of sliding a figure in any direction.
Click the Octagon to see
Translation.
Reflection (flip)
The result of a figure flipped over a line.
Click on this trapezoid to see reflection.
The result of a figure flipped over a line.
Which shapes show reflection, translation, or rotation?