Triangle quartet II

Three coloured equilateral triangles share three vertices. Prove that the triangle formed by their centres is also equilateral.1This puzzle is also known as Napoleon’s Theorem.

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Solution by Jaihind Singh.
Proof by Jaihind Singh that circumcircles intersect at one point.


We are the 4 triangles quartet
As you can see
We have a lot of angles
Without being caught in a tangle
We live together carefully
We believe in rimes and poetry
We know what the poet meant to say
And find the words along the way
We are the 4 so pretty
You will love our harmony


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