1. Sử dụng hằng đẳng thức

x² - 6x + 8

= ( x² - 2.x.3 + 3² ) - 1

= ( x - 3 )² - 1

= ( x - 3 )² - 1²

= ( x - 3 - 1 ) ( x - 3 + 1 )

= ( x - 4 ) ( x - 2 )

2. Phương pháp tách một hạng tử

x² - 6x + 8

= x² - 4x - 2x + 8

= ( x² - 4x ) - ( 2x - 8 )

= x ( x - 4 ) - 2 ( x - 4 )

= ( x - 4 ) ( x - 2 )

3. Phương pháp nhẩm nghiệm

x² - 6x + 8

= ( x - 4 ) ( x - 2 )

chiều 3h mình giải cho chắc thế!

m ^a  .  m ^b =  m ^{a + b}

l i k e cho mình nha bạn

13. C

14. C

15. C

16. A

17. A

18. C

19. C

20. B

1. I'm quite tall but you are taller (as........as)

I'm as tall as you.

2. Hoa and Tim are both 13 years old (the same .................as)

Tim is the same age as Hoa.

3. She speaks E very well, and her sister speaks well too (as ...........as)

She speaks English as well as her sister.

4.They lived here for a long time but we've lived here longer (as ...........as)

They haven't lived here as long as us.

5. My birthday is 12 August. Tom's birthday is 12 August (the same ............as)

My birthday is the same day as Tom's.

6. Sandra spent 100 dollar, but Susan spent 120 dollars (as ...........as)

Sandra didn't spend as much money as Susan did.

7. Nam drive carefully, but his sister drive more carefully (as ...............as)

Nam doesn't drive as carefully as his sister.

8. We left the meeting at 10 p.m , they left the meeting at 10p.m too (The same .........as)

We left the meeting at the same time as they did.

V.

1. This coat isn't warm enough for me to wear in winter.

2. That chair isn't strong enough to stand on.

3. This bed isn't wide enough for you to sleep in.

4. There weren't enough cups for me to make coffee for everyone.

5. He didn't have enough time to finidh the examination.

VI.

1. The book is so interesting that I have read it many times.

2. She is such a beautiful girl that we all like her.

3. The coffee was such hot coffee that I couldn't drink it.

4. The bridge is so low that car can't go under it.

5. He is such an intelligent pupil that he can answer all my questions.

Câu 6 bạn thiếu đề bài nhé!

1. People are talking about her everywhere.

-> She is being talked about every where.

2. He is watching them work.

-> They are being watched working.

3. They will give me gifts for my fifteenth birthday.

-> Gifts will be given to me for my fifteenth birthday.

4. You must wash those jeans by hand.

-> Those jeans must be washed by hand.

5. She will tell you what time the train leaves.

-> You will be told what time the train leaves.

He has slept since 10 o'clock.

Tuổi con cách đây 4 năm là : ( 34 - 24 ) : 2 = 5 ( tuổi )

Tuổi con hiện nay là : 5 + 4 = 9 ( tuổi )

Tuổi mẹ hiện nay là : 9 + 24 = 33 ( tuổi )

     Đáp số : Con : 9 tuổi .

                : Mẹ : 33 tuổi .

tick nha.