user-avatar
tram233
2 năm trước
Vẽ ra phía ngoài tam giác nhọn ABC các tam giác vuông cân ABD, ACE ở B và C. Gọi M là trung điểm của DE. Kẻ DN, AH, MI, EK cùng vuông góc với BC tại N, H, I, K. Chứng minh rằng: a) I là trung điểm của NK b) Tam giác DNB = tam giác BHA, tam giác EKC = tam giác CHA. c) Tam giác CMB vuông cân ở M
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

Read the paragraphs below and the summary which follows. (3ms) Air pollution is a cause of ill-health in human beings. In a lot of countries there are laws limiting the amount of smoke which factories can produce. Although there isn’t enough information on the effects of smoke in the atmosphere, doctors have proved that air pollution causes lung diseases. The gases from the exhausts of cars have also increased air pollution in most cities. The lead in petrol produces a poisonous gas which often collects in busy streets surrounded by high buildings. Children who live in areas where there is a lot of lead in the atmosphere can’t think as quickly as other children and are clumsy when they use their hands. There are other long-term effects of pollution. If the gases in the atmosphere continue to increase, the earth’s climate may become warmer. A lot of the ice near the Poles ma melt and may cause serious floods.

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team