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9.10 Rotations. United Streaming Video. Dynamic Worksheets. A rotation is a transformation that turns a figure about a fixed point called the center of rotation. . The measure of the rotation is the angle of rotation. .
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9.10 Rotations United Streaming Video Dynamic Worksheets
Arotation is a transformation that turns a figure about a fixed point called the center of rotation. The measure of the rotation is the angle of rotation. All rotations will be counter-clockwise unless otherwise specified.
Rotate ABC with points A(1,-1) B(1,-4) C(5,-4) 90° about the origin. Example
Rotational Symmetry A figure has rotational symmetry if you can rotate it 180°, or less, so that its image matches the original figure. The angle (or its measure) through which the figure rotates is the angle of rotation.
To find the Angle of Rotation If a figure has rotational symmetry, find the angle of rotation by dividing 360 by how many times the figure “matches” itself. A regular triangle will have 120° rotational symmetry because 360 / 3 = 120.
Does a regular hexagon have rotational symmetry? Yes, because 360 / 6 = 60. A hexagon has 60° rotational symmetry.
Things to Remember about rotations… 90° (x, y) -> (-y, x) 180° (x, y) -> (-x, -y) 270° (x, y) -> (y, -x) For Example: B(2, 3) 90° B’ (-3, 2) 180° B” (-2, -3) 270° B”’(3, -2) 360° B””(2, 3) Hot Potatoes