https://www.khanacademy.org/math/geometry/xff63fac4:hs-geo-transformation-properties-and-proofs/hs-geo-symmetry/v/example-rotating-polygons 2021-02-16T16:08:13Z Intro to rotational symmetry Sal checks whether various figure are symmetrical under a 180 degrees rotation. Sal Khan video https://cdn.kastatic.org/googleusercontent/sjvgJaDero2jqNHDjxN-uzBv5YH0m-lNVi5mvuC-MjglbNRSb3wvcN30eVZYHAo5Y_EEdm0jBKuhW4EB_T8CRvY6 Intro to rotational symmetry Sal checks whether various figure are symmetrical under a 180 degrees rotation. https://cdn.kastatic.org/ka-youtube-converted/P35LyN9g0oI.mp4/P35LyN9g0oI.mp4 248 Transformation by rotation https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/v/rotating-points 2023-05-12T21:01:01.897246564Z Rotating points Positive rotation angles mean we turn counterclockwise. Negative angles are clockwise. We can think of a 60 degree turn as 1/3 of a 180 degree turn. A 90 degree turn is 1/4 of the way around a full circle. The angle goes from the center to first point, then from the center to the image of the point. video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Rotating points Positive rotation angles mean we turn counterclockwise. Negative angles are clockwise. We can think of a 60 degree turn as 1/3 of a 180 degree turn. A 90 degree turn is 1/4 of the way around a full circle. The angle goes from the center to first point, then from the center to the image of the point. https://cdn.kastatic.org/ka-youtube-converted/0NYbQPcdxg8.mp4/0NYbQPcdxg8.mp4 110 Transformation by rotation https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/v/points-after-rotation 2021-02-16T16:08:13Z Rotating shapes Sal is given a triangle on the coordinate plane and the definition of a rotation about the origin, and he manually draws the image of that rotation. video https://cdn.kastatic.org/googleusercontent/ryzpJhKhWrS1aIVhgEGBk4l1pSuU5cwCYGGk3g3Z_n65H4DZIhy6iKwT75LvrxuldQ4_i68sddB0kyK07XCJhwN3 Rotating shapes Sal is given a triangle on the coordinate plane and the definition of a rotation about the origin, and he manually draws the image of that rotation. https://cdn.kastatic.org/ka-youtube-converted/6nUMiJfHLSA.mp4/6nUMiJfHLSA.mp4 492 Transformation by rotation https://www.khanacademy.org/math/geometry-home/transformations/old-transformations-videos/v/rotation-of-polygons-example 2020-06-23T07:22:40Z Rotation examples (old) An older video where Sal finds the images of shapes under various rotations, and where he determines the rotations that take one shape to another. Sal Khan video https://cdn.kastatic.org/googleusercontent/oMXlMlllgsgQGTjqI0mnp8acV0hMocajz0dJLTBa7lDfNxPSm2ai8ANBkyFqsCLiw-a4z_7QoOE6NZ-phQ4J8rfP Rotation examples (old) An older video where Sal finds the images of shapes under various rotations, and where he determines the rotations that take one shape to another. https://cdn.kastatic.org/ka-youtube-converted/Hur3v1hrX3U.mp4/Hur3v1hrX3U.mp4 147 Transformation by rotation https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-transformations-intro/a/intro-to-rotations 2022-06-13T22:23:00.945663613Z Rotations intro Learn what rotations are and how to perform them in our interactive widget. article https://www.khanacademy.org/math/cc-eighth-grade-math/geometric-transformations/rotations-8th/a/rotations-review 2023-12-11T22:13:00.981327266Z Rotations review Review the basics of rotations, and then perform some rotations. article https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/e/rotations-1 2026-04-07T23:36:17.218592739Z Rotate shapes Given a figure on the coordinate plane and the definition of a rotation about the origin, manually draw the image of that rotation. Tomer Gal exercise https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/v/defining-rotation-example 2023-05-12T21:01:01.897246564Z Determining rotations To see the angle of rotation, we draw lines from the center to the same point in the shape before and after the rotation. Counterclockwise rotations have positive angles, while clockwise rotations have negative angles. Then we estimate the angle. For example, 30 degrees is 1/3 of a right angle. video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Determining rotations To see the angle of rotation, we draw lines from the center to the same point in the shape before and after the rotation. Counterclockwise rotations have positive angles, while clockwise rotations have negative angles. Then we estimate the angle. For example, 30 degrees is 1/3 of a right angle. https://cdn.kastatic.org/ka-youtube-converted/6pH-7pciYU8.mp4/6pH-7pciYU8.mp4 177 Transformation by rotation