3 'nearSQUARES'

Topic:
Geometry
Here are three shapes that can become square. For each shape can you devise a measure of how close the shape comes to being square? Can you devise a single measure of 'closeness to square' that works for more than one shape? Give an example, or explain why not? Can you devise a single measure of 'closeness to square' that works for all three shapes? Give an example, or explain why not? What questions could / would you put to your students based on this applet?
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