median
don steward
mathematics teaching 10 ~ 16

Thursday, 20 July 2017

grid kites and rhombuses

Pierre van Hiele advocates constructing the special quadrilaterals by means of reflections and rotations
that way the properties are easily deduced (e.g. "because of the mirror line") from the constructions

this has been explored more fully by Michael Villiers in South Africa, using an interactive geometry package

the powerpoint goes through the constructions (but it's probably better demonstrated with an interactive package)





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