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tranthithaoquyen88
2 năm trước
1. a. vẽ góc xAy có số đo 60độ. b. Vẽ góc x'Ay' đối đỉnh với góc xAy. c. Vẽ tia phân giác At của góc xAy. Tính số đo góc tAx. d. Vẽ tia At' là tia đối của tia At. Tia At' có là tia phân giác của góc x'Ay' không?vì sao?
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