Now let's look at a 180° rotation about the spot (0, 0). Since it doesn't matter which direction we go, we'll use CCW. Use the 'Mode' button to set this up now ... move the centre spot to (0, 0), and change the rotation to 180° CCW. The object (the brown dot) will look like it is being rotated by 180° clockwise, around the centre spot, to its image, the the blue dot. This graph will allow you to find out what happens to individual coordinates as they are rotated 180° CCW. Follow the instructions here. When you are done the exercise, close the exercise window and then check your conclusion.
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