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Glide Reflections. Review. Mrs. Erickson. Composition of Transformations. When two transformations are performed, one following another, that is called a composition of transformations . First you get A’, then you get A’’. Glide Reflections.
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Glide Reflections Review Mrs. Erickson
Composition of Transformations When two transformations are performed, one following another, that is called a composition of transformations. First you get A’, then you get A’’.
Glide Reflections Glide Reflection: A composition of transformations that consist of a line reflection and a translation in the direction of that line (in either order).
Glide Reflections y ΔABC: A (1,2) B (5,3) C (3,4) Reflect in y-axis T0,-4 --------------------------- T0,-4 Reflect in y-axis C’ (-3,4) C (3,4) B (5,3) B’ (-5,3) -4 A’ (-1,2) A (1,2) C’’ (-3,0) x B’’ (-5,-1) A’’ (-1,-2)
Glide Reflections y ΔPQR: P (2,1) Q (4,1) R (3,4) Reflect across y=x T-3,-3 --------------------------- T-3,-3 Reflect in y-axis R (3,4) Q’ (1,4) -3 R’ (4,3) P’ (1,2) -3 Q’’ (-2,1) P (2,1) Q (4,1) x R’’ (1,0) P’’ (-2,-1) y=x
Glide Reflections y ΔABC: A (1,2) B (5,3) C (3,4) Reflect in y-axis T5,-5 C’ (-3,4) C (3,4) 5 B (5,3) B’ (-5,3) A’ (-1,2) A (1,2) -5 x C’’ (2,-1) B’’ (0,-2) Not a glide reflection. The translation is not parallel to the y-axis. A’’ (4,-3)
Isometry An isometry is a transformation that preserves distance. Direct isometry: preserves distance and orientation. Opposite isometry: preserves distance but changes the orientation from clockwise to counterclockwise, or counterclockwise to clockwise.
Done! Did that horn scare you? … what about now?