Euclid's Elements • Book I, Prop 47
Pythagorean Theorem (Windmill Proof)
In right-angled triangles, the square on the hypotenuse equals the sum of the squares on the legs.
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A
along Thales' Arc (Right angle is 100% preserved)
∠BAC = 90.0° STRICT
c²
b²
c²
b²
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