Thales’ theorem

Let $A$ and $B$ be two points and $C$ a point on the semicircle above them. Then the angle $ACB$ is ${90}^{\circ }$.

Title	Thales’ theorem
Canonical name	ThalesTheorem
Date of creation	2013-03-22 12:45:24
Last modified on	2013-03-22 12:45:24
Owner	mathwizard (128)
Last modified by	mathwizard (128)
Numerical id	6
Author	mathwizard (128)
Entry type	Theorem
Classification	msc 51-00
Related topic	AngleOfViewOfALineSegment
Related topic	ProvingThalesTheoremWithVectors
Related topic	AreaOfSphericalCalotteByMeansOfChord