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 * Symmetry! **

 2) Rotational Symmetry
__Reflection Symmetry/ Line Symmetry __
 * Definition : ** A type of symmetry in which one half of the figure is the mirror image of the other.


 * Line of Symmetry: ** A line that divides a figure into two equal parts, each of which is the mirror image of the other.


 * Examples: **

The left half of the butterfly is the mirror image of the right half. The dotted red line is the line of symmetry in this example.

The figure can have a line of symmetry that is diagonal or horizontal too!





**A figure can also have more than one line of symmetry!** For example:

[|Reflection Symmetry Printable Worksheet #1] [|Reflection Symmetry Printable Worksheet #2] [|Reflection Symmetry Printable Worksheet #3]
 * <span style="color: #1e70a6; font-family: Verdana,Geneva,sans-serif; font-size: 110%;">Worksheets: **

__<span style="color: #257755; font-family: Verdana,Geneva,sans-serif; font-size: 160%;">Rotational Symmetry __
 * <span style="color: #257755; font-family: Verdana,Geneva,sans-serif; line-height: 1.5;">Definition: ** <span style="font-family: Verdana,Geneva,sans-serif; line-height: 1.5;">When a figure can be rotated some amount and it still looks the same.

media type="custom" key="23681966" align="left" width="120" height="120"

<span style="font-family: Verdana,Geneva,sans-serif;">
 * <span style="color: #257755; font-family: Verdana,Geneva,sans-serif; font-size: 110%; line-height: 1.5;">Another example: **

<span style="font-family: Verdana,Geneva,sans-serif;">This figure has can be rotated 3 times and it will look the same each time.


 * <span style="color: #257755; font-family: Verdana,Geneva,sans-serif; font-size: 110%;">More examples: **

<span style="font-family: Verdana,Geneva,sans-serif;">Notice that **some figures can have rotational __and__ reflection symmetry.** <span style="font-family: Verdana,Geneva,sans-serif;">From the examples above, the first and third figures have reflection symmetry as well:

<span style="font-family: Verdana,Geneva,sans-serif;">Does this shape have rotational symmetry?



<span style="font-family: Verdana,Geneva,sans-serif;">Answer: No. <span style="font-family: Verdana,Geneva,sans-serif;">**If a shape fits itself once, it has no rotational symmetry.** If we rotate the clover, it will not look the same until it is back in it's original position, so it only fits itself once.

<span style="display: block; font-family: Verdana,Geneva,sans-serif; font-size: 110%; text-align: center;">[|Interactive activity: Click here to explore more about rotational symmetry] <span style="display: block; font-family: Verdana,Geneva,sans-serif; font-size: 110%; text-align: center;">[|Rotational Symmetry Quiz: Click here to to test your knowledge on rotational symmetry!]

<span style="color: #008080; display: block; font-family: Verdana,Geneva,sans-serif; font-size: 160%; text-align: center;">__Where else can we find symmetry?__ <span style="font-family: Verdana,Geneva,sans-serif;">There is reflection and rotational symmetry everywhere! Symmetry is all around us in the real world.

<span style="font-family: Verdana,Geneva,sans-serif;">Here are some examples of reflection symmetry in nature:

<span style="font-family: Verdana,Geneva,sans-serif;">Rotational symmetry in nature:


<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">[|Watch a fun video of symmetry in the world!] <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">[|Draw your own picture online with reflection and/or rotational symmetry!] __<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Sources: __
 * http://www.sparklebox.co.uk/3351-3360/sb3360.html
 * http://www.icoachmath.com/math_dictionary/Reflectional_Symmetry.html
 * http://www.icoachmath.com/math_dictionary/Line_of_Symmetry.html
 * http://www.emathematics.net/transformations.php?def=reflectional
 * http://langfordmath.com/ECEMath/Geometry/SymIntroText.html
 * http://www.emathematics.net/transformations.php?def=reflectional
 * http://www.math-only-math.com/line-symmetry.html
 * http://labspace.open.ac.uk/mod/resource/view.php?id=418068
 * http://www.mathsisfun.com/definitions/rotational-symmetry.html
 * http://www.cimt.plymouth.ac.uk/projects/mepres/book8/bk8i15/bk8_15i3.htm
 * http://euler.slu.edu/escher/index.php/Introduction_to_Symmetry
 * http://dev.physicslab.org/Document.aspx?doctype=5&filename=ModernAtomicNuclear_RotationalReflectionSymmetries.xml
 * http://vector-magz.com/illustrations/clover-outline-clipart-item-1/
 * http://www.123rf.com/photo_14680976_close-up-of-a-dry-plane-tree-leaf--platanus-acerifolia--platanus-hispanica--isolated-on-white-2-imag.html
 * http://social-i.net/themathsfactor/maths-in-nature/
 * http://www.craigcrawford.co.uk/pages/galleries/landscape/scotland.php?gall_id=61
 * http://blsciblogs.baruch.cuny.edu/symmetries/