Question

Answer 1

Ta có:

 \(\widehat{xOz}=\widehat{tOy}\left(đối.đỉnh\right)\\ \Leftrightarrow90^o-x=180^o-4x\\ \Leftrightarrow-x+4x=180^o-90^o\\ \Leftrightarrow3x=90^o\\ \Leftrightarrow x=30^o\)

Answer 2

Do 2 góc zOx và góc yOt là 2 góc đối đỉnh

\(\Rightarrow\widehat{zOx}=\widehat{yOt}\)

\(\Rightarrow90^o-x=180^o-4x\)

\(\Rightarrow-x+4x=180^o-90^o\)

\(\Rightarrow3x=90^o\)

\(\Rightarrow x=30^o\)