This graph allows you to explore rotations of polygons. Use the 'Mode' button to set the center spot to (0, 0), and leave the rotation set at 90° CCW. Next, choose 'Draw'. Click in several places in the upper right part of the graph to construct a polygon. The more times you click, the more sides it will have. Now choose 'Mode' again, and this time you will be able to move one of the polygons around. Assume it's the original object. What happens with the other polygon, the image? What do you notice? Here is what you should discover, regardless of how many sides the polygon has:
- Wherever the object is, the image is the same distance from the centre spot.
- The size and shape of the image are the same as the size and shape of the object.
This is also true for any center spot, and any degree of rotation. Try it and see.
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