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Time Estimate


Main Idea

15 min


Does this work for concave non-regular polygons?

Partition the polygons into the minimum number of triangles.

Justification for the concave non-regular polygon interior angle sums.

Step-by-step guide:

1. Have participants draw concave polygons and measure the angles, similar to the previous situation.
Possible Problems and Concerns:
Drawing the triangles in the concave polygons may be a bit tricky. Have the participants label the triangles as they make them.
Internet Sources:

http://www.mste.uiuc.edu/m2t2/algebra/regs.gsp is a Geometer's Sketchpad file of regular polygons. Resources for this unit are available at http://www.mste.uiuc.edu/m2t2/algebra/

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