Răspuns :
[tex]\it AD\perp BC \Rightarrow \widehat{ADC}=90^o\\ \\ \\ \widehat{DAB}=57^o\ (complementul \ lui\ 43^o\ \hat\imath n\ \Delta DAB)\\ \\ \\ \\ \widehat{BAC}=90^o\ ( deoarece\ \Delta ABC- dreptunghic\ \hat\imath n\ A)[/tex]
[tex]\it AD\perp BC \Rightarrow \widehat{ADC}=90^o\\ \\ \\ \widehat{DAB}=57^o\ (complementul \ lui\ 43^o\ \hat\imath n\ \Delta DAB)\\ \\ \\ \\ \widehat{BAC}=90^o\ ( deoarece\ \Delta ABC- dreptunghic\ \hat\imath n\ A)[/tex]