Biết tia OA nằm giữa tia OB và OC, (1) $\widehat{BOC}={{120}^{0}}$,(2)$\widehat{BOA}-\widehat{AOC}={{40}^{0}}$. Số đo $\widehat{BOA}$ là:

Biết $\widehat{xOy}={{80}^{0}},\widehat{yOz}={{40}^{0}},\widehat{xOz}={{120}^{0}}$. Khẳng định nào dưới đây đúng?

Cho biết tia Oz nằm giữa tia Ox và Oy, $\widehat{xOy}={{40}^{0}},\widehat{xOz}={{30}^{0}}$. Số đo góc zOy là:

Khẳng định nào dưới đây sai?

Lúc 15 giờ, kim giờ và kim phút của đồng hồ tạo với nhau một góc như thế nào?

Lúc 6 giờ, kim giờ và kim phút của đồng hồ tạo với nhau một góc như thế nào?

Cho hình vẽ sau:

Nêu tên góc vuông có trong hình.

Cho hình vẽ sau:

Đọc tên các góc nhọn có trong hình.

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