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Teaching the Geometry of the Plane Using Origami

Masashi Sanae & Stephen ElliffRitsumeikan High School

2010 Singapore Math Challenge

Origami

ORIGAMICS2

The Basic Drawing Method

①perpendicular bisector

③angle bisector

②perpendicular to line segment through a point

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Basic Folding

①perpendicular bisector

③angle bisector

②perpendicular to line segment through a point

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Incenter

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Circumcenter

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Centroid

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Excenter

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Application- All Sides Overlap

We can fold a polygon so that all sides overlap

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A Triangle

Incenter

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A Quadrilateral with One Open Side

Excenter11

A Quadrilateral with One Open Side

Excenter12

Circumscribed Polygon

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Polygon

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Polygon

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Geometry with Salt

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Reference

M.Sanae’S HomePage (Masashi Sanae)

http://izumi-math.jp/sanae/

Origami and Mathematics （ Konichi

Kato ）

http://izumi-math.jp/K_Katou/origami/origami.htm

Thank you for listening.

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