Quandaries and Queries

Calculus, 12th grade

HOw do i prove this : FOr any triangle, if you make 3 equillateral triangles using the sides of the the original triangle, the central points of the 3 tringles another triangle that is equillateral.

Please Help,


Hi david,

The result is called Napoleon's theorem. There are dozens of elementary proofs; these can be found in Geometry books that cover geometry beyond the basic theorems of Euclid. For example Coxeter's Geometry Revisited, or his Introduction to Geometry. You can also look on the Cut the Knot Web Site.

Chris and Penny

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