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mytam2092003
2 năm trước
hai xe oto khởi hành cùng một lúc từ 2 địa điểm A và B ,cùng chuyển động đều về địa điêm C , biết AC =120km ; BC =90km. Xe khởi hành từ A đi vần tốc 50km/h . Muốn 2 xe đến điểm C cùng một lúc , xe khởi hành từ B phải chuyển động với vận tốc v2 bằng bao nhiêu ?
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