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Rotations. p. 12-13 8/15/13. Review- Left Side p. 12. 1) Using point (1,2), complete the following transformation ( x , y )→( x - 2, y + 1 ) 2) Reflect A(-9, -3) over the y-axis. 3) Reflect B(-7, 0) over the y-axis. Rotations p. 13.
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Rotations p. 12-13 8/15/13
Review- Left Side p. 12 1) Using point (1,2), complete the following transformation ( x, y )→( x - 2, y + 1 ) 2) Reflect A(-9, -3) over the y-axis. 3) Reflect B(-7, 0) over the y-axis.
Rotations p. 13 • Objective: Rotate figures in the coordinate plane.
Rotations • A rotation is a 1)rigid transformation in which a 2)figure is rotated, or turned, about a fixed point. The3)center of rotation is the fixed point (0,0). A rotation does not change the size or shape of the figure.
Rotations are described using degrees and directions • Degree: 90ᵒ, 180ᵒ, 270ᵒ • Direction: Clockwise or Counterclockwise
Rules Clockwise Counterclockwise
Left Side Practice • Use the point (-2,3) 1. Rotate counterclockwise 90 degrees 2. Rotate clockwise 180 degrees 3. Rotate counterclockwise 270 degrees • A triangle has vertices of A (0,0); B (3,0); and C (3,4) 4. Rotate the triangle 90 degrees counterclockwise about the origin. Name the the coordinates of the vertices using A‘, B‘, and C'