Vì \(\widehat{yOx}\) và \(\widehat{bOx}\) là 2 góc kề bù nên \(\widehat{yOx}+\widehat{xOb}=180^o\)
\(50^o+\widehat{xOb}=180^o\)
\(\widehat{xOb}=130^o\)
Vì \(\widehat{bOx}\) và \(\widehat{bOa}\) là 2 góc kề bù nên \(\widehat{bOa}+\widehat{xOb}=180^o\)
\(\widehat{bOa}+130^o=180^o\)
\(\widehat{aOb}=50^o\)
Vì \(\widehat{bOa}\) và \(\widehat{yOa}\) là 2 góc kề bù nên \(\widehat{bOa}+\widehat{yOa}=180^o\)
\(50^o+\widehat{yOa}=180^o\)
\(\widehat{yOa}=130^o\)
b)Ta có :\(\widehat{bOa}=\widehat{xOy}\left(50^o=50^o\right)\)
\(\widehat{yOa}=\widehat{xOb}\left(130^o=130^o\right)\)
a) Ta có: \(\widehat{xOb}+\widehat{xOy}=180^0\)(hai góc kề bù)
nên \(\widehat{xOb}=180^0-50^0=130^0\)
\(\Leftrightarrow\widehat{aOy}=130^0\)
\(\Leftrightarrow\widehat{aOb}=50^0\)
b) \(\widehat{aOb}=\widehat{yOx}\left(=50^0\right)\)
\(\widehat{xOb}=\widehat{yOa}\left(=130^0\right)\)
