MathDB
Geometry (flanders '96)

Source:

August 9, 2004
geometrytrigonometry

Problem Statement

In triangle ΔADC\Delta ADC we got AD=DCAD=DC and D=100D=100^\circ. In triangle ΔCAB\Delta CAB we got CA=ABCA=AB and A=20A=20^\circ. Prove that AB=BC+CDAB=BC+CD.