Đáp án:
Giải thích các bước giải:
$\text{$\widehat{xOt}+\widehat{yOt}=180°$(Hai góc kề bù)}$
$⇒\widehat{xOt}+130°=180°$
$⇒\widehat{xOt}=50°$
$\text{Mà $\widehat{yOt}=\widehat{xOz}=130°$}$
$⇒\widehat{yOz}=\widehat{xOt}=50°$
$\text{Ta có : $\widehat{yOz}+\widehat{xOt}+\widehat{zOt}=180°$}$
$⇒\widehat{xOt}+\widehat{xOt}+\widehat{zOt}=180°$
$⇒2\widehat{xOt}+\widehat{zOt}=180°$
$⇒2.50°+\widehat{zOt}=180°$
$⇒\widehat{zOt}=180°-100°$
$⇒\widehat{zOt}=80°$