Bài 2 : Tìm m để các đường thẳg sau đây đồng quy : (d1) : 5x + 11y = 8 ; (d2) : 4mx + (2m – 1)y = m + 2 ; (d3) : 10x – 7y = 74
Bài 3: Cho tam giác ABC có AB = 10 , AC = 24 , BC = 26 a/ Chứng minh tam giác ABC vuông. b/ Tính các góc B ; C. c/ Tính chiều cao AH và các đoạn mà chiều cao đó chia ra trên BC.
Bài 4: Cho tam giác ABC vuông tại A và có AB >AC, đường cao AH. Trên nửa mặt phằng bờ BC chứa điểm A, vẽ nửa đường tròn đoừng kính BH cắt AB tại A, vẽ nửa đường tròn đường kính HC cắt AC tại F
a. Chứng minh tứ giác AEHF là hình chử nhật
b. Chứng minh AE.AB=AF.AC
Bài 5: Một mảnh vườn hình chữ nhật có chu vi 50m, nếu tăng chiều dài thêm 3m và tăng chiều rộng thêm 2m thì diện tích tăng thêm 65m2. Tính chiều dài, chiều rộng của mảnh vườn.
I. Choose the word which is pronounced differently from the others.
1. A. benefit B. deny C. interactive D. Internet
2. A. wonderful B. violent C. opinion D. Control
3. A. faded B. planted C. watched D. handed
II. Choose the word whose main stress pattern is not the same as that of the others.
1. A. access B. purpose C. remote D. wander
2. A. respond B. commercial C. computer D. Education
III. Vocabulary, grammar and structure:
1. She thinks chatting on the Internet is time …………..
A. consume B. consumer C.consuming D. consumption
2. By learning English, you can get access to the worl’s…………….
A. develop B. development C. developing D. developed
3. We can communicate with friends by ……………of e- mail.
A. means B. paths C. methods D. uses
4. The Internet nowadays has become an important means of………….
A. relation B. communication C. combination D. connection
5. Your teacher writes poems or stories, …………she?
A. doesn’t B. won’t C. didn’t D. don’t
6. Going swimming in the summer is very interesting, …………it?
A. is B. are C. isn’t D. aren’t
7. Thanks to the Internet, people can get the………..information.
A. late B. later C. lately D. latest
8. The “Kien Thuc Ngay Nay” is _______read by both teenagers and adults
A. wide B. widely C. widen D. widened
9. I hope after the course I can read newspaper ________ English.
A. in B. by C. with D. on
10.They have to work hard _________ Monday ________ Saturday.
A. from / to B. on / to C. on / from D. to / from
11. We stayed at home………it rained heavily.
A. and B. but C. so D. because
12. They didn’t understand the matter; ………, they didn’t ask for help.
A. moreover B. however C. and D. but
13. Her sister _____as a presenter in the local television station, doesn’t she?
A. works B. is working C. has worked D. worked
14. Do you mind _____me an evening newspaper on the way home?
A. buy B. to buy C. buying D. bought
15. You bought this pair of trouser yesterday, ______?
A. didn’t you B. weren’t you C. did you D. were you
16. Most children enjoy _________advertisements on TV
A. to watch B. watch C. to watching D. watching
17. Every thing is okay, ________ ?
A. is it B. are they C. isn’t it D. hasn’t it
18. What have you learned since you _____ here ?
A. came B. come C. is coming D. have come
IV. Fill in each numbered blank with one suitable word or phrase:
Television is an important invention of the 20th century. It has been so (1) ………… that now we can’t imagine what life would be like if there was no television. Television is a major mean of (2) ………… It bring pictures and sounds from around the world into million of homes. Television (3)………… can see and learn about people, places and things in far away lands. Television widens our knowledge by introducing us to new ideas which may lead us to new hobbies and recreations. In addition to the news, television (4) ………… us with a variety of programs that can satisfy every taste. Most people now seem to like (5)………… their evenings watching television .It is more convenient for them to stay at home watching television than to go out for amusement elsewhere.
1. A. popular B. inconvenient C. fast D. important
2. A. information B. communication C. connection D. combination
3. A. seers B. audience C. lookers D. viewers
4. A. provides B. to provide C. provide D. provided
5. A. spend B. spent C. spending D. to spend
V.Chọn phương án (A hoặc B, C, D) ứng với từ/ cụm từ có gạch chân cần phải sửa:
1. Your brother likes watching documentaries, isn't he?
A B C D
2. I dislike to play soccer, it seems quite boring for me.
A B C D
3. Mrs. Lan never listens to music on the radio, doesn't she ?
A B C D
4. You didn't read the article about environment, have you?
A B C D
Một máy biến thế gồm cuộn sơ cấp có 500 vòng cuộn thứ cấp có 50000 vòng ,đạt ở hai đầu một đường dây tải điện để truyền đi một công suất điện là 1000KW,hiệu điện thế đặt vào hai đầu cuộn sơ cấp là 220V .
a) Tính hiệu điện thế ở hai đầu cuộn thứ cấp
b) Biết dây dẫn có điện trở là 220 Ω .Tính công suất hao phí do tỏa nhiệt trên đường dây .