The slider controls of the angle of rotation of triangle ABC around the origin, which is A'B'C'. Move the slider to see how the triangle rotates.
1) What are the coordinates of A', B', and C' when r = 90º? 2) What are the coordinates of A',B', and C' when r = 180º? 3) What are the coordinates of A',B', and C' when r = 270º? 4) What are the coordinates of A',B', and C' when r = 360º? 5) What patterns do you recognize to transform A to A' for each of these transformations?