 The geometry that studies the symmetry and all forms of their transformation of it is called Transformation Geometry. edtech2.boisestate.edu

 Teacher: Students Repeat:  Teacher: A-B-C Students Repeat: A-B-C

 Here and there Here and there And everywhere And everywhere We can see We can see Symmetry! Symmetry! Our two eyes Our two eyes See butterflies See butterflies A perfect square A perfect square A teddy bear A teddy bear The number 3 The number 3 The letter Z The letter Z Most any car Most any car A shiny star A shiny star Up and down Up and down And all around And all around We can see We can see Symmetry! Symmetry

 Once when you where to look symmetry is all around you. Book TalkBook Talk  By Loreen Leedy

 Symmetry: Having equal parts in two or more direction  Reflective Symmetry:  The identical reflection of two sides. (Flip)  Rotation Symmetry:  The rotation around a point.  Translation Symmetry:  The slides but not turns.

 How many movement do you need?

Names of Shapes Lines of Symmetry (Asymmetrical) Lines of Symmetry 0123 More than 3Infinity Cloud Butterfly Heart Happy Face Triangle Square Pentagon Hexagon Octagon Decagon Circle Parallelogram Rectangle

 A still lake reflects sky and trees in Canada.  Photograph by Raymond Gehman

Washington’s North Cascade National Park

 If an object does not emit its own light, it can reflect the light in order to be seen.

 Absorb  Reflect  Transmitted  The person sees reflected light.

 What are they?  How do we use them?

 A Famous Italian inventor and artist named Leonardo da Vinci used to keep a dairy. However, he wanted his thoughts secret so he wrote in mirror writing. Do you know why that is?  ml ml

Objects or Shapes’ Name Circle What does it look like before exploration? Pre image Explain the reason why? What does it look like after Exploration? Image Did you have a misconception? Notes Can you write your name in mirror writing? Yes No Equilateral triangle Yes No

 The normal is the imaginary line that is perpendicular 90 degree to the surface.  LAW of REFLECTION  The of incidence = of reflection.

 To view an image of an object mirror, you must sight along a line at the image location.  As you sight at the image, light travels to your eye along the path shown in the diagram below. The diagram shows that the light reflects off the mirror in such a manner that the angle of incidence is equal to the angle of reflection.

 Each person sees the image due to the reflection of light off the mirror in accordance with the law of refletion.  When each line of sight is extended backwards, they will intersect at the same point, which the image point of the object.

 Specular Reflection - from a smooth, mirror- like surface.  Defuse Reflection- If the surface is rough, the rays of light are reflected in many directions.  The angles of incidence and reflection are still equal but the rays appear to be scattered.

 A bundle of many rays of light travel together with the same intensity and direction?  Where have you seen it?

Rotational Symmetry- If the object or the image can be rotated and it still looks the same.

 How many matches there are as you go once around is called the order.

 The London Eye with an order of symmetry of 32.

 Following are facts about rotational symmetry:  All figures have at least one order of rotational symmetry. (Rotating a figure 360º will always match the original figure).

 Search for four symmetry pictures from recycling magazines or newspapers.  Clip and paste them in your math journal.  Write a reflection if the object is symmetrical.  If so, where is the line of symmetry? Construct it!  What kind of symmetry is?

WordsDefinition Symmetry The identical reflection of two sides. Transformation or Image (Reflection, Translation, Rotation, and dilation) A transformation changes a figure into another figure. Reflection A transformation in which a figure is reflected in a line called the line of reflection. (mirror image) Rotation A transformation in which a figure is rotated about a point called the center of rotation. The angle of rotation The number of degrees a figure rotates. Translation A transformation in which a figure slides but does not turn. Every point of the figure moves the same distance and in the same direction. Vertex of an angle The point at which the two sides of an angle meet. Vertex of a polygon A point at which two sides of a polygon meet. The plural of vertex is vertices. Congruent Figures that have the same size and the same shape

 Half vs. Whole  Equal vs. Not Equal  Vertical vs. Horizontal  Repeat- Match (folding shapes)  Reflection-Flip- Mirror Image  Rotate-Turn

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