( 2a - 1)²= (2a)² - 2.2a.1 + 1² = 4a² - 4a +1 

1. We sometimes use a dictionary in class.

Do you sometimes use a dictionary in class ?

 2. My friends are friendly.

Are  your friend friendly?

 3. School finishes at three o'clock. 

Does school finish at three o'clock?

4. You live near me.

Do you live near me?

5. He likes Pop music.

Does he like Pop music?

6. Jack does his homework before dinner. 

Does Jack do his homework before dinner?

7. I and my sister play tennis in school on Wednesday afternoon.

Do you and your sister play tennis in school on Wednesday afternoon?.

8. I’m a singer. 

Are you a singer?

9. My mother teaches art. 

Does your mother teach art?

10. He plays tennis after school

Does he play tennis after school?.

11. It’s nine o'clock. 

Is it nine o'clock?

12. We have lunch at school. 

Do you have lunch at school?

13. Now is seven o’clock . 

Is now seven o'clock?

14. We go to bed at nine o´clock. 

Do you go to bed at nine o'clock?

(y + 2)² = y² + 2.y.2 + 2² = y²+ 4y +4

a

    75 - 7.(x- 8) = 12

⇒ 7. (x - 8)       = 63

⇒        x- 8        = 9

⇒         x            = 17

Vậy x = 17

c

okay. Thanks bn nhìu nha 

Quang last cooked when he was sick 

8x³ - 27= (2x)³ - 3³ = (2x - 3). ( 4x² +6x + 9)