Question

1. Cho hai goc ke \(\widehat{AOB}\) va \(\widehat{BOC}\) co tong so do cua hai goc la \(^{140^0}\) biet \(\widehat{AOB}\) co so do lon hon so do cua goc \(\widehat{BOC}\) la \(^{20^0}\)

a, Tinh \(\widehat{AOB,}\widehat{BOC}\)

b, Ve tia phan giac Om cua \(\widehat{AOB}\), tia phan giac On cua \(\widehat{BOC}\). Tinh \(\widehat{mOn}\).

Answer 1

a: \(\widehat{AOB}=\dfrac{\left(140^0+20^0\right)}{2}=80^0\)

nên \(\widehat{BOC}=60^0\)

b: \(\widehat{mOn}=\widehat{mOB}+\widehat{nOB}=\dfrac{1}{2}\cdot140^0=70^0\)