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Bàl 6. Cho tam giác ABC có A(8; 0), B(0; 6), C(9; 3). Gọi H là chân duong cao từ C xuống cạnh AB. a) Tìm phương trình cạnh AB và đưong cao CH. b) Gọi I, K lần lưot là hình chiếu của C trên Ox và Oy. Chứng minh I, H, K thẳng hàng. Giúp e bài này với ạ
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 Exercise: Choose the best answer: 1. Many young people are fond of -------------- football and other kinds of sports. A. play B. to play C. playing D. played 2. They couldn’t help -------------- when they heard the little boy singing a love song. A. laughing B. to laugh C. laugh D. laughed 3. Your house needs -------------- . A. redecorated B. redecorating C. being redecorated D. to redecorate 4. I remember -------------- them to play in my garden. A. to allow B. allow C. allowing D. allowed 5. It was a nasty memory. Do you remember both of us wearing sunglasses to avoid -------------- by the supervisors? A. to recognize B. to be recognized C. recognizing D. being recognized 6. I can’t bear thinking back of that time. I’d rather ---------- equally. A. treat B. be treated C. have treated D. treating 7. Did you accuse Nam of --------- a plate? Well, I saw him ------ it off the table with his elbow. A. break/ knock B. breaking/ knocking C. to break/ to knock D. breaking/ knock 8. We found it very difficult -------------- with Gamma. A. to work B. work C. working D. worked 9. I can’t read when I am traveling. It makes me -------------- sick. A. feel B. to feel C. felt D. feeling 10. I need -------------- what’s in the letter. Why don’t you let me -------------- it? A. to know/ to read B. know/ read C. to know/ read D. knowing/ read 11. I suggest -------------- some more mathematical puzzles. A. do B. to do C. doing D. done 12. We regret -------------- you that we cannot approve your suggestion. A. inform B. to inform C. informing D. informed 13. The driver stopped -------------- a coffee because he felt sleepy. A. have B. to have C. having D. had 14. Have you ever considered -------------- a pharmacist? A. become B. becoming C. to become D. became 15. You had better -------------- at home until you feel better. A. staying B. stayed C. to stay D. stay 16. I remember -------------- my mother said the grass in the garden needed --------------. A. to hear/cutting B. hear/cut C. heard/to cut D. hearing/ cutting 17. Peter sometimes help his sister --------------. A. do homework B. to do homework C. with homework D. all are correct 18. I would rather -------------- at home than --------------out with you. A. staying/going B. to stay/ to go C. stay/go D. stayed/went 19. I would rather you --------------. A. drive B. to drive C. drove D. driven 20. She didn’t say a word and left the room. A. She left the room without saying a word B. She leaving the room without saying a word C. She left the room saying a word D. She left the room to say a word. 21. My father wanted me -------------- a pilot. A. become B. to become C. becoming D. became 22. Please wait a minute. My boss is busy -------------- something. A. write B. writing C. to write D. to writing 23. My teacher doesn’t allow us --------- while he is explaining the lesson. A. talk B. to talk C. talking D. talked 24. We have plenty of time. We needn’t -------------- A. hurry B. to hurry C. hurrying D. hurried 25. I promised -------------- on time. I mustn’t -------------- late. A. be/be B. to be/to be C. to be/ be D. be/to be 26. Mary and I are looking forward -------------- you. A. of seeing B. for seeing C. to seeing D. to see 27. I’m sure that he knows -------------- this new machine. A. to use B. using C. how using D. how to use 28. Psychiatrists and doctors have failed -------------- people not to drink. A. to tell B. telling C. tell D. told 29. The students are used to -------------- in the school library. A. working B. work C. to work D. worked 30. Our room needs -------------- up. A. tidied B. to tide C. tidy D. tidying 31. Mercury’s low gravity makes you -------------- very light in a spaceship. A. feel B. feeling C. to feel D. felt 32. “ Was the test long?”. “ Yes, John was the only one -------------- it” A. to finish B. finishing C. finished D. finish 33. A lots of needs -------------- to the house before anyone can move in. A. be done B. doing C. to do D. done 34. It is about time you -------------- harder for the next exam. A. worked B. working C. work D. to work 35. If he really doesn’t feel like ------------ now, I suggested that he should go out for some fresh air. A. work B. to work C. worked D. working

IV. Read the passage and do the work assigned. Millions of people (1) ___________the world want to learn English. Many of them go to the US and other English (2) ___________ countries to study at language schools, especially (3) ___________ Summer. There are thousands of different schools. There are often courses (4) ___________children, teenagers and adults. If you go to a language school, you should try (5) ___________ English as much as possible. Students can stay with a local family. This is a good opportunity (6) ___________your English and to learn a lot about everyday life. You should try to talk to students from other countries. This will help you to improve your English (7) ___________it will also show how important English is for international (8) ___________. Fill in each blank by circling A, B, C or D. (1 pt) 1. A. at 2. A. speak 3. A. at 4. A. to 5. A. to speak 6.A. to improve 7. A. but 8. A. commune B. around B. spoke B. on B. with B. speak B. improved B. so B. common C. on C. speaking C. for C. between C. spoke C. improving C. and C. coming D. to D. spoken D. in D. for D. speaking D. improve D. therefore D. communication Decide True (T), False (F) or Not Given (N.G).(1 pt) 1. Many people want to learn English. ___________ 2. There are hundreds of different English speaking schools. ___________ 3. Students can stay in many dormitories. ___________ 4. Only adults can learn English. ___________

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