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Reflection

Rigid Motions: Reflection

On the coordinate grid above, I have created an example of a reflection, which is the last of the three rigid motions mentioned.  In geometry, a reflection is defined as a transformation in which each point of the pre-image has an image that is equidistant from the line of reflection.  The line of reflection must also form a 90 degree angle with any segment connecting any point on the pre-image with its image.  My reflection example displays the pre-image figure ABCDEFGH in quadrant two and the image of figure A'B'C'D'E'F'G'H' in quadrant four.  It is shown that figure ABCDEFGH was reflected over the line y = x and the image of figure A'B'C'D'E'F'G'H' ended up in quadrant four.  This reflection can be verified as accurate, because each vertex of the pre-image and image are the same distance from the line of reflection.  Thus, this aspect in forming a reflection proves the example to be correct. 

Reflections Video