Hình bn tự vẽ nha!!!
Ta có: \(\widehat{xOy}\) ${và}$ \(\widehat{x'Oy}\) là 2 góc kề bù
⇒ \(\widehat{xOy}\)+\(\widehat{x'Oy}\)=$180^{o}$
⇒ $100^{o}$+\(\widehat{x'Oy}\)=$180^{o}$
⇒ \(\widehat{x'Oy}\)=$180^{o}$-$100^{o}$
⇒ \(\widehat{x'Oy}\)=$80^{o}$
Lại có: Ot' là tia pg của \(\widehat{x'Oy}\) (gt)
⇒ \(\widehat{x'Ot'}\)=\(\widehat{yOt'}\)=$\frac{\widehat{x'Oy}}{2}$=$\frac{80^{o}}{2}$=$40^{o}$
Mặt khác: Tia Ot là tia pg của \(\widehat{xOy}\) (gt)
⇒ \(\widehat{xOt}\)=\(\widehat{yOt}\)=$\frac{\widehat{xOy}}{2}$=$\frac{100^{o}}{2}$=$50^{o}$
Ta có: \(\widehat{tOt'}\)=\(\widehat{yOt'}\)+\(\widehat{yOt}\)=$40^{o}$+$50^{o}$=$90^{o}$
