bài 2 a, A1 =180-75=105

            D= 75 => D1=105

            C=60

             B=90

b, A1+B1+C1+D1=105+105+60+90=360

C,tổng các góc ngoài của tứ giác bằng 360 

bài 3. 

a, AB=AD (GT) nên điểm A thuộc dựng trung trực của BD

CB=AD (GT) nên điểm C thuộc đường trung trực của BD 

=> AC là đường trung trực của BD

b, 

xét tam giác BAC và DAC

BC=CD

AC

AB=AD

=> tam giác BAC=DAC( ccc) 

=> B=D ( 2 GÓC TƯƠNG ỨNG )

trong tứ giác ABCD ; A+B+C+D = 360 

=> B+D=200

=> B=D=100 độ

100 do minh chua chac la dung

Đây mà là toán à?

về thầy cô :

Viên phấn nào trên tay 
Thầy dạy em học chữ 
Bụi phấn nào bay bay 
Vương tóc thầy trắng xóa 

Bao mùa thu đi qua 
Thầy xưa nay đã già 
Khai trí em thêm sáng 
Cho cây đời nở hoa 

Từng lời giảng yêu thương 
Bao lớp trẻ xa trường 
Gói hành trang thêm nặng 
Nghĩa tình thầy vấn vương 

Mai lớn khôn nên người 
Khi nào em quên được? 
Công ơn người đi trước 
Dìu dắt chúng em theo. 

thank you nhưng sorry nhé bạn có chép trên gogle ko vậy hay bạn tự sáng tác 100%

Hjhj hey. Mk ko lm dk

III.
1. B 
2. B
3. B
4. C
5. C
6. C 
7. A
8. C
9. D 
10. C
11. A
12. D
VII.
1. went
2. to tell
3. eat
4. will be
5. going
6. allows
7. watching
8. did you do
9. to finish
10. don't have to get 
11. taught
12. spend/ playing
13. got
14. didn't go
15. built
16. Did you meet
17. to fly
18. did you do / went
19. bought
20. be/ be
21. to socialize
22. to read
23. to see
VIII.
1. You ought not to watch TV too late.
2. My sister prefers walking to cycling.
3. They enjoy traveling to Nha Trang on their vacation.
4. How about seeing a detective film ?
5. Ba plays basketball skillfully.
6. Do you like milk for breakfast ?
7. I don't like durians.
8. Would you like to collect stamps?
9. Lan invites me to have diner with her.
10. I don't have to do my homework today.
11. How heavy are you ?
12. His brother is safe cycler.
13. My father drives carefully.
14. What is matter with her ?
15. How tall are you ?
16. What is wrong with him ?
IX.
1. cavity
2. would
3. so
4. should
5. How heavy
6. much
7. Why
8. fluently
9. in
10. much
11. did
12. either
13. badly
14. to go
15. before
16. to
17. Would you like to 
18. films
19. spends
20. five-minute
XI.
1. B
2. A
3. C
4. D
5. A
6. C
7. C
9.D
10. C
XII.
1. A
2. C
3. A
4. D 
5.B
XIII.
1. What's this table's weight ?
2. What's your father's height ?
3. What was Alice's height last time ?
4. What was your weight last month ?
5. What's the wall's height ?
XIV.
1. can too
2. didn't either
3. will too
4. aren't either
5. So did
6. Neither can
7. So do 
8. So are
9. Neither did
10. don't either
XV.
1. Some of them planted fruit tree and vegetables.
2. The children shouldn't often go to amusement center.
3. Video games can be addictive.
4. Teenagers around the world like television most.
5. Children should brush their teeth after meals. 

đề dài thì e tách từng phần ra, đăng lên đây và các bạn sẽ giúp e nhé

III

1) Should Jahn be helped with the sewing ?

2) Judy's car is being repeared by the mechanic .

3) Must the test be finished before ten ?

4) A computer is used to that job nowadays .

5) All travel expenses for this training course must be paid by employers .
 

6) Were they taken in by her story .

7) I was kept waiting for half an hour by the bank manager .

8) Has this word been spelt wrongly .

9) He will be seen off at the airport by all his friends ,

10) Beer used to be druck for breakfast in England years ago .

11) The letter might have been sent to the wrong address .

12) The floor was being cleaned when I arrived .

13) The hold is being dug on the wrong side of the road .

14) Your money is going to be stolen if you're not careful .

15) Have you ever been asked for your opinion ?

Bài 2 : 

\(\frac{2008}{2009}+\frac{2009}{2010}+\frac{2010}{2011}+\frac{2011}{2008}\)và 4