user-avatar
haihang201
2 năm trước
cho tam giác ABC vuông tại B có AB=15cm, AC=20cm, đường cao AH, đường phân giác DB(h thuộc BC; D thuộc AC) a) c/m tg ABC đồng dạng tg HBA, từ đó suy ra AH.BC=AC.AB b) tính độ dài các đoạn thẳng BC, AH, BH, c) gọi I là giao của AH và BD, tìm tỉ số S tgABD/S tgHBI d trên cạnh AB lấy điểm M, trên cạnh AC lấy điểm N sao cho BM=CN, gọi K là giao điểm của MN và BC. c/m AB/AC=KN=KM mk đg cần gấp ạ!!
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

I.Choose the best answer 1. _______ he is old, he wants to travel around the world. A. In spite of B. Although C. Despite D. Because 2. ________ I came to England, I couldn’t speak a work of English. A. Since B. After C. While D. Before 3. They left the house ________ saying good-bye to their mother. A. before B. after C. during D. in 4. She is looking for a new job _______ she is tired of doing a routine job day after day. A. despite B. although C. because D. All are correct 5. He’s still going to school _________ his injury. A. even though B. although C. in spite of D. even though 6. He left home early ________ he could arrive at the station on time. A. because of B. in order to C. although D. so that 7. We will wait here ______ he comes back. A. while B. until C. before D. after 8. We could reach the house ______ the road was flooded. A. although B. whether C. as if D. even 9. My mother looks _______ she is tired. Perhaps she didn’t sleep well last night. A. like B. although C. until D. as if 10. Our teacher speaks slowly _______ we may understand him. A. because B. in order to C. so that D. or 11. ________ these cars are cheap, they last a long time. A. Because B. in order that C. Although D. after 12. You should give the iron time to heat up _______ you iron your clothes. A. because B. so that C. even though D. before 13. You need good shoes to go hiking in the mountains _______ the ground is rough and hard. A. because B. so that C. before D. even though 14. ________ he is tired, he can’t work longer. A. Because B. Even though C. Although D. Beside 15. ______ he is so busy with his work, he always finds time to go to the concert every week. A. If B. Since C. Although D. Because 16. I haven’t seen Tom _____ he gave me this book. A. since B. for C. until D. Before 17. He had left _____ I came. A. when B. while C. since D. by the time 18. Our visit to Japan was delayed _____ my wife’s illness. A. because B. because of C. thanks to D. Though 19. I couldn’t unlock it ______ I had the wrong key. A. because B. so that C. although D. so 20. ______ rain or snow, there are always more than fifty thousand fans at the football games. A. Despite B. Although C. Because D. Since

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