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9.3 – Perform Reflections. Reflection:. Transformation that uses a line like a mirror to reflect an image. Line of Reflection:. Mirror line in a reflection. A reflection in a line m maps every point P in the plane to a point , such that:.
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Reflection: Transformation that uses a line like a mirror to reflect an image Line of Reflection: Mirror line in a reflection
A reflection in a line m maps every point P in the plane to a point , such that: • If P is not on m, then m is the perpendicular bisector of • If P is on m, then
Reflect point P(5, 7)in the given line. x – axis P(5, 7) becomes P A reflection in the x-axis changes (x, y) into _______ (x, –y)
Reflect point P(5, 7)in the given line. y – axis P(5, 7) becomes P A reflection in the y-axis changes (x, y) into _______ (–x, y)
Reflect point P(5, 7)in the given line. y = x P(5, 7) becomes P A reflection in the y = x changes (x, y) into _______ (y, x)
Graph the reflection of the polygon in the given line. x – axis
Graph the reflection of the polygon in the given line. y – axis
Graph the reflection of the polygon in the given line. y = x (–1 , –3) (–3, –1) (2, –4 ) (–4, 2) (3, 0) (0, 3)
Graph the reflection of the polygon in the given line. x – axis
Graph the reflection of the polygon in the given line. x = –1
Graph the reflection of the polygon in the given line. y = 2
Transformation that turns a figure about a fixed point Rotation: Center of Rotation: The point that the rotation happens around Angle of Rotation: Degree the figure is rotated counterclockwise
A rotation about a point P through an angle of x° maps every point Q in the plane to a point such that: • If Q is not the center of rotation, then • and Q x° P
A rotation about a point P through an angle of x° maps every point Q in the plane to a point such that: • If Q is the center of rotation, then Q
State if the rotation is 90°, 180°, or 270° counter-clockwise. 180° Counter-clockwise degree of rotation: _______
State if the rotation is 90°, 180°, or 270° counter-clockwise. 90° Counter-clockwise degree of rotation: _______
State if the rotation is 90°, 180°, or 270° counter-clockwise. 270° Counter-clockwise degree of rotation: _______
6.Find the value of each variable in the rotation. 4 x = z = 3 y = z + 2 y = 3 + 2 y = 5
6.Find the value of each variable in the rotation. 4s = 24 s = 6 r = 2s – 3 r = 2(6) – 3 r = 12 – 3 r = 9
HW Problems 9.3 #7