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Transformations. Reflections. A transformation of a geometric figure is a change in its position, shape, or size. In geometry, we talk about reflections (flips), translations (slides), rotations (turns), and dilations. Translation. Reflection. Dilation. Rotation.
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A transformation of a geometric figure is a change in its position, shape, or size. In geometry, we talk about reflections (flips), translations (slides), rotations (turns), and dilations. Translation Reflection Dilation Rotation
In a transformation, the original figure is the preimage; the resulting figure is an image. Rotation preimage image
An isometry is a transformation in which the preimage and image are congruent. *HIGHLIGHT
C’ is the image of C ; C’D’ corresponds to CD • A transformation maps a figure onto its image CDEF C’D’E’F’ (CDEF “maps onto” C’D’E’F’)
A reflection(or flip) is an isometry in which a figure and its image have opposite orientation.
line r A “reflection in line r”is the reflection around some imaginary line r.
B r A = A’ B’ A reflection in line r is a transformation for which the following are true: If a point A is on line r, then the image of A is A itself (A’ = A). If a point B is not on line r, then r is the perpendicular bisector of BB’.
For this figure, draw its reflection image in each line: x-axis L’ line r J’ I’ K’
For this figure, draw its reflection image in each line: L’ line r I’ K’ y = 2 J’
For this figure, draw its reflection image in each line: line r x = -1 K’ I ’ J’ L’