\(\widehat{xOy}+\widehat{yOz}=180^o\left(2.góc.kề.bù\right)\\ \Leftrightarrow\widehat{xOy}+75^o=180^o\\ \Leftrightarrow\widehat{xOy}=180^o-75^o=105^o\)
Do \(\widehat{xOy}\) kề bù \(\widehat{yOz}\) nên:
\(\widehat{xOy}+\widehat{yOz}=180^o\Rightarrow\widehat{xOy}=180^o-\widehat{yOz}=180^o-75^o=105^o\)
Ta có: \(\widehat{xOy}\) kề bù với \(\widehat{yOz}\)
\(\Rightarrow\widehat{xOy}+\widehat{yOz}=180^o\)
Mà: \(\widehat{yOz}=75^o\)
\(\Rightarrow\widehat{xOy}=180^o-\widehat{yOz}=180^o-75^o=105^o\)
