a, \(\widehat{xOy}\) + \(\widehat{yOz}\) = 1800; \(\widehat{xOy}\) = \(\widehat{yOz}\) ⇒ 2\(\widehat{xOy}\) = 1800
⇒ \(\widehat{yOz}\) = \(\widehat{xOy}\) = 1800 : 2 = 900
b, Các cặp góc bằng nhau là:
\(\widehat{yOz}\) = \(\widehat{xOm}\); \(\widehat{yOz}\) = \(\widehat{xOy}\); \(\widehat{yOz}\) = \(\widehat{zOm}\);
\(\widehat{zOm}\) = \(\widehat{mOx}\); \(\widehat{zOm}\) = \(\widehat{xOz}\);
\(\widehat{xOm}\) = \(\widehat{xOy}\);