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Reasoning About Geometry


Recognising Transformations

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Given the effect of an isometry or similarity on a point, on a directed line segment, on a circle, or on a quadrilateral, how do you identify the type of transformation and justify that with geometrical reasoning?

The applet provides 8 transformations to be identified. Notes on using the applet are under construction. Contact john.mason @ open.ac.uk for assistance
​What is important is the reasoning: seeking invariants and recognising how much information you need to be sure.

Then thee is the issue of reconstructing the transformation for yourself, and working out what the composite of two of them would be.
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