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honcta
2 năm trước
Bài 4: Cho tam giác ABC cân tại A. Trên cạnh BC lần lượt lấy hai điểm M, N sao cho BM = CN. a) Chứng minh rằng : Tam giác AMN là tam giác cân . b) Kẻ BH AM ( H AM ), kẻ CK AN ( K AN ). Chứng minh rằng BH = CK, AH = AK. c) Gọi O là giao điểm của BH và CK. Tam giác OBC là tam giác gì ? d) Khi và BM = MN = CN, hãy tính số đo các góc của tam giác ABC. giúp mình với ! mình vote 5 sao
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UNIT 1: MY HOBBIES I. Put the verbs in brackets into the present or future simple 1. I ( help) ................................... you with these heavy bags. 2. Mary ( buy) ................................ a new houses for her family next year. 3. I hope you (get) ..............................good grades next semester. 4. The visitors probably ( visit) ..................................... the museum tomorrow afternoon. 5. She promises that she (not tell) ......................................anyone what happened. 6. My grangparents often (watch) ..............................TV in the evening. 7. These boys (walk) ......................................................................to school everyday? 8. We (smell) ....................................................something burning. 9. He ( not be) ............................................a lazy boy. 10. His children ( never play) ................................... computer games. 11. They (be) .....................................usually at homr on Sundays. 12. These students often ( have) ........................................lunch in the school canteen. 13. Dorothy sometimes (help) ...........................................her mother to do the housework. 14. What he ( usually have) ...............................................for breakfast? _ Rice and boiled eggs or meat. 15. He ( look) ...........................................tired and hungry now. 16. Don’t worry. You all (know) ..........................................the result tomorrow. 17. You ( have) ......................................... time to help me when I need you? 18. Do you think he ( recognize) .............................................. me? 19. Perhaps he ( arrive) .............................................in time for lunch. 20. I am sure that you (like) ........................................our new house. II. Use the present or future simple form of each verb in brackets to complete the passage There are four people in my family. We (1. have) .......................... different hobbies. My father (2.like) .......................... playing badminton. He (3.play) .................................it almost everyday. My mother (4. not like) ..................................... this sport. She (5. enjoy) .................................. walking. Every morning she (6. walk) .............................for about two kilometers. Next year, I (7. join ) ........................... her. My younger sister (8. love) .................................reading books. There is a big bookshelf in her room. I (9. not like) ...................................her books because they are usually picture books. She says she (10. read) ...................................other kinds of books when she

Câu 1 : Biết 3x+2(5-x) =0 ,giá trị của x là a/ -8 b/-9 c/ -10 d/ kết quả khác Câu 2 : Chọn câu trả lời đúng (2x3-3xy +12x).( bằng a/ b/ c/ d/ Câu 3 : Tích của đa thức :4x5+7x2 và đơn thức -3x3 là a/ 12x8+21x5 b/ -12x8+21x5 c/12x8-21x5 d/-12x8-21x5 Câu 4 : Tích của đơn thức :x2 và đa thức ; 5x3 –x- là : a/5x6 +x3 - x2 b/ -5x5-x3- x2 c/ 5x5-x3- x2 Câu 5 : Tích của đơn thức x và đa thức 1-x là : a/x2-x b/ 1-2x c/ x2+x d/ x-x2 Câu 6 : Xác định đúng sai : a/3x.(5x2-2x+1)=15x3-6x2-3x b/(x2+2xy-3)(-xy)=-xy3-2x2y2+3xy c/-5x3(2x2+3x-5)=-10x5-15x4+25x3 d/(-2x2+ y2-7xy).(-4x2y2)=8x4y2+3xy4+28x2y3 Câu 7: Giá trị của x thoả mãn : 2x.(5-3x)+2x(3x-5) -3(x-7)=3 là : a/ 6 b/-6 c/ 4 d/ -4 Câu 8 : Các biểu thức sau không phụ thuộc vào giá trị của biến đúng hay sai : a/2(2x+x2)-x2(x+2)+(x3-4x+3) b/x(x2+x+1)-x2(x+1) –x+5 c/3x(x-2)-5x(x-1)-8(x2-3) d/2y(y2+y+1)-2y2(y+1)-2(y+10) Câu 9 :Tính và thu gọn : 3x2(3x2-2y2)-(3x2-2y2)(3x2+2y2) dược kết quả là : a/ 6x2y2-4y4 b/ -6x2y2+4y4 c/-6x2y2-4y4 d/ 18x4 -4y4 Câu 10 : Tính (x-y)(2x-y) ta được : a/ 2x2+3xy-y2 b/ 2x2-3xy+y2 c/ 2x2-xy+y2 d/ 2x2+xy –y2 Câu 11: Điều kiện để cho biểu thức là một phân thức là: A. x 1; B. x = 1; C. x 0 D. x = 0 Câu 12: Phân thức bằng với phân thức là: A. B. C. D. Câu 13: Phân thức đối của phân thức là: A. B. C. D. Câu 14: Phân thức nghịch đảo của phân thức là: A. B. C. D. Câu 15 : Chọn kết quả đúng ; (2x+3y)(2x-3y) bằng a/ 4x2-9y2 b/ 2x2-3y2 c/ 4x2+9y2 d/ 4x-9y

Exercise 1: Choose the best answer 1. My wedding ring ………… of yellow and white gold. A. is made B. is making C. made D. maked 2. This house ……………….for 2 years. A. was built B. has been built C. has built D. built 3. References …………. in the examination room. A. not are used B. is not used C. didn’t used D. are not used 4. Mary ………….. in Boston. A. are born B. were born C. was born D. born 5. There’s somebody behind us. I think we are ………………. A. being followed B. are followed C. follow D. following 6. Have you …………….. by a dog? A. bite B. ever been bit C. ever been bitten D. bit 7. The room is being ………….. at the moment. A. was cleaned B. cleaned C. cleaning D. clean 8. Mr. Wilson is . . . . . . . . as Wilie to his friend. A. knowed B. knew C. known D. is known 9. When…………..? In 1928. A. penicillin was discovered B. did pencillin discoved. C. was penicillin discoverd D. did pencillin discover. 10. All the homework be doing _____________ at home. A. should do B. should done C. should be done D. should Exercise 2: Give the correct form of verb in passive voice 1. English ( speak) ___________ in many countries. 2. I (not allow)_________________ to stay out too late. 3. My homework ( finish) _____________ before 7 p.m yesterday. 4. The accidents ( cause)_____________ by this man last night. 5. This meal ( prepare) _____________ by my mother at the moment. 6. This box ( not open) _____________ yet. 7. The cakes (cut) _____________into 8 pieces already. 8. This postcard ( send) _____________to Italy by my Italian friend 3 days ago. 9. These cakes ( make) _____________ by my sister in the kitchen now. 10. This organization (found) _____________ by a businessman 3 years ago.

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