Prerequisites for Marion Walter's Theorem

There are several ways to approach the problem and your approach will probably depend on which mathematical topics you are familiar with.

- You can use classical geometry.  For that, you'll need  a solid background in proportionality, areas of polygons, and similarity.   
- You can use analytic geometry.  You'll need to know how to find equations of lines and how to solve linear systems.
- You could use vector geometry. You'll need to know how to find vector equations of lines  and how to use determinants to find areas.

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