x - y = 5

=>(x - y)^{2 ​}= 25

​=> x²  - 2xy + y^{2 ​} = 25

​=> 15 - 2xy ^​ =​ 25

=>  2xy = 15 - 25

=> 2xy = - 10

=> xy = -10 : 2

=> xy = -5

x^{3 ​} - y^3​  =​ ( x - y ) ( x ²  - xy + y²)​​

^​​​ => x³- y^{3 ​}= 5 . ( -5 . 15 )

​= >x ^{3  ​} -​ y ^3​ = - 375. ​

17.How much rice and how many beef do you want? -> much
18.She’d like a dozen eggs and any vegetables. -> 
19.Can you to go to the supermarket for me ,Hoa ?  -> bỏ TO đi 
20.We need eight hundred gram of beef. -> grams 
21.What would you like buying at the canteen ?  -> to buy
22.There is a apple on the table. -> an 

1. D

2. C
3. D
4. B
5. C

11. B

12. D

13. D

14. A

15. B
16. A
17. C

18. D
19. B

20. D

1) What is your telephone number?

2)What time do we get up?

3) How many classrooms are there in her school?

4) How is our school?

5)  - Where does Mrs Nhung live?

     - Where is Mrs Nhung home address? 

1. Hello, this is Dr Smith's office. Who is speaking ?

2.  Hurry up ! The train is coming.

3. The Earth goes round the Sun.

4. Some animals don't eat   during the winter.

5.  - What is Oanh doing at the moment ?

    - She is cooking . She usually cooks dinner for her family.

Cho số phức z=-1+2i. Số phức z ¯  được biểu diễn bởi điểm nào dưới đây trên mặt phẳng tọa độ?

A.Q(-1;-2)

B. P(1;2)

C.N(1;-2)

D.M(-1;2)

bt 34 là ở bài dựng hình mà bạn 

Dựng hình thang ABCD, biết góc D = 90^o , đáy CD = 3 cm, cạnh bên AD = 2 cm, cạnh bên BC = 3cm.