# Thales' theorem

- Author:
- Zoltán Kovács

`LocusEquation[a⊥b,C]`

asks GeoGebra where to put point *C*to ensure that the triangle is right at

*C*. Thales' theorem states that if (and only if)

*C*is a point of the circumcircle of the diameter

*AB*, then the triangle is right.