Without moving the point of reflection, rotate the shape (using the angle of rotation slider) so that point A is at (-3,1). What angle did you rotate by? Was it a clockwise or counter clockwise rotation?

Without moving the point of reflection, rotate the shape (using the angle of rotation slider) so that point A is at (-1,-3). What angle did you rotate by?[br][br]Now draw a circle using the circle with center through point [icon]/images/ggb/toolbar/mode_circle2.png[/icon] tool. First click on the center of rotation which is the point (0,0) (also called the origin), then click point A on the preimage (brown). Don't forget to change back to the select  [icon]/images/ggb/toolbar/mode_move.png[/icon] tool before moving the slider.

As you rotate the figure (without moving the center of rotation) notice which points stay on the circle. Draw a new circle so with center at the origin that passes through point B. rotate the figure a bit. Do you see the pattern? Draw another circle with center at the origin and passing through a point on the preimage. Rotate the figure a bit. What is the pattern?