Respuesta :

Setor9
12) Angle ACD= Angle ABC+ Angle CAB ====> You MAY end here
That is, Angle ACD= 132+21
            Angle ACD= 153

13) Angle ABC+ Angle BAC=  Angle ACD====> You MAY end here
That is,     Angle ABC +16=143
                                   -16= -16
                Angle ABC=127