The Compendium Geometry is an eBook providing facts, formulas and explanations about geometry.

Generalized Pythagorean Theorem

The generalized Pythagorean theorem is valid not only for right triangles but also for any kind of triangle.

a2 = b2 + c2 ± 2bp
b2 = a2 + c2 ± 2cq
c2 = a2 + b2 ± 2ar

with

p .... projection of c onto b
q .... projection of a onto c
r .... projection of b onto a


Last Update: 2010-12-06