Dudeney's Cross-to-Isosceles-Right-Triangle Dissection

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This Demonstration gives Dudeney's (1897) dissection of a four-piece hinged cross into an isosceles right triangle.
Contributed by: Izidor Hafner (March 2011)
Based on work by: Greg N. Frederickson
Open content licensed under CC BY-NC-SA
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Details
Henry Ernest Dudeney (1857-1930) was a self-educated English mathematician. Collections of his puzzles appeared in five books.
G. N. Frederickson, Dissections: Plane & Fancy, New York: Cambridge University Press, 1997.
G. N. Frederickson, Hinged Dissections: Swinging & Twisting, New York: Cambridge University Press, 2002 p. 19.
Permanent Citation
"Dudeney's Cross-to-Isosceles-Right-Triangle Dissection"
http://demonstrations.wolfram.com/DudeneysCrossToIsoscelesRightTriangleDissection/
Wolfram Demonstrations Project
Published: March 7 2011