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thuphuong09122001
2 năm trước
Cho ΔABC vuông tại A có AB= 3cm, AC= 4cm. Vẽ đường cao AH a) Chứng minh ΔHAC đồng dạng ΔABC. Từ đó suy ra AH.BC=AB.AC b) Tính AH c) Trên AH lấy điểm K sao cho AK= 1,2cm. Từ K kẻ đường thẳng song song BC cắt AB và AC lần lượt tại M và N. Tính diện tích tứ giác BMNC
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Exercise 1: Read the article about Sean Murphy. Are sentences 1-7 "Right" (A) or "Wrong" (B)? If there is not enough information to answer "Right" (A) or “Wrong" (B), choose "Doesn't say" (C). For questions 1-7, mark A, B or C on your answer sheet. At home Seen Murphy reads the late news on British television at 11 o'clock each evening. "This is a good time for a new programme because we can report the early news from America and the late news from Europe. I still arrive home before midnight because the journey from the Television Centre to my home in north London only takes six minutes. My family are all asleep when I get in, but I usually make a drink of hot milk and read a book for about an hour. 'I always get up to have breakfast with my three children before they catch the school bus. Then I take the newspapers and go back to bed for a short time. Later on, I go for a swim- Seen Murphy newsreaders speand too much time sitting downt I sometimes go running. I've done the London Marathon twice. That's a race of over 40 kilometresLGnished each time, but I wasn't among the first! I start work after lunch at two o'clock, when I go to my office. The rest of the day is spent planning the programme, but I always try to go home for an hour to see my cvhildren before they go to bed. Example: 0. The late news begins at 11 o'clock every evening. A. Right B. Wrong C. Doesn't say I. Seen Murphy lives in London. Right C. Doesn't say B. Wrong 2. Sean's wife gives him a hot drink when he arrives home after work. Right C. Doesn't say B. Wrong 3. Seen takes his children to school in the morning. B. Wrong 4. Seen likes to go swimming with his colleagues from work. B. Wrong Right C. Doesn't say Right Doesn't say 5. Seen has won the London Marathon. Right B. Wrong C. Doesn't say 6. Seen's working day begins in the afternoon. Right B. Wrong C. Doesn't say 7. Seen usually leaves the office for an hour during the evening. Right Exercise 2: Read the desciptions of some holiday words. What is the word for each one? The first letter is already there. There is one space for each other letter in the word. For questions 36-40, write the words on your answer sheet. (KET extra) Example: 1. If you go on a camping holiday, you may sleep in this. B. Wrong C. Doesn't say tent 2. This is where you lie in the sun and go swimming. be as 3. You can pack all your holiday clothes in this. 4. Without this cannot go to some countries. 51

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