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Geometry with McCarthy. Section 9-1: Reflections. What you’ll learn . Objectives: Identify and draw reflections. Identifying Reflections. A reflection is a transformation that moves a figure across a line. Not a reflection. Line of reflection. Line of reflection.
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Geometry with McCarthy Section 9-1: Reflections
What you’ll learn Objectives: Identify and draw reflections.
Identifying Reflections A reflection is a transformation that moves a figure across a line.
Line of reflection Line of reflection
Reflections in the coordinate plane P(x, y) P(x, y) P’(-x, y) P(x, y) P’(y, x) P’(x, -y) Across the x-axis Across the y-axis Across the line y=x (x, y) (x, -y) (x, y) (-x, y) (x, y) (y, x)
Example Reflect the figure with the given vertices across the given line. M(1, 2), N(1, 4), P(3, 3); y-axis D(2, 0), E(2, 2), F(5, 2), G(5, 1); y=x
Isometry An isometryis a transformation that does not change the shape or size of a figure.