Đặt:x=2k,y=3k,z=5k

=> (2k)(3k)(5k)=810

=> 30k^3 = 810

=> k^3 = 810 / 30 = 27

=> k = căn bậc 3 của 27 

=> k = 3

x = 2k => x = 6

y = 3k => y= 9

z = 5k => z= 15

Vậy x=6,y=9,z=15

Question 3: Mark the word that differs from the others in terms of primary stress.

Question 4: Mark the word that differs from the others in terms of primary stress.

Question 5: Susan: "How long have you been practising the piano?" Mike: "______"

Question 6: Smoke from vehicles accounts ______ a significant portion of air pollution in cities around the world.

Question 7: We ______ to go everywhere by car, but now we use public transport more.

Question 8: This year, we're having a big family get-together to ______ my cousin turning eighteen.

Question 9: The band ______ music is amazing made all the spectators dance and sing along.

Question 10: ______ the high cost, we decided to buy tickets to the exhibition.

Question 11: Factories are ______ the environment by producing large amounts of waste and greenhouse gases.

Question 12: After the earthquake, several houses ______ and hundreds of people became homeless.

Question 13: We're ______ at our esteemed bank in Birmingham, UK.

Question 14: If you're motivated and eager to learn more, we want to hear ______ you!

Question 15: Send your application ______ banking@jobs.com.

Question 16: Don't miss this opportunity to launch your ______ in the banking industry.

Healthy living is not just about avoiding illness; it’s about leading a lifestyle that allows you to feel your best every day, both physically and mentally. In a world where convenience often overshadows wellness, adopting a balanced approach to living is essential for long-term health. Here are some key aspects to living a healthy life.

Physical activity is essential for a healthy life. Regular exercise helps in maintaining a healthy weight, strengthens muscles and bones, improves cardiovascular health, and boosts mental well-being. A combination of aerobic exercises like running, swimming, or cycling, and strength training exercises like weight lifting or yoga, can help improve overall fitness. Even simple activities like walking or stretching daily can significantly enhance your health.

That book belongs to Nam.
→ That is Nam's book.

What is the age of Peter?
→ How old is Peter?

No one in our class is taller than Nam.
→ Nam is the tallest in our class.

Mr. Hong drives very carefully.
→ Mr. Hong is a very careful driver.

Does your father cycle to work?
→ Does your father get to work by bicycle?

Why don't we go to the movies tonight?
→ What about going to the movies tonight?

She doesn't have classes on Sunday.
→ She never has classes on Sunday.

How wide is BaDmh square?
→ What is the width of BaDmh square?

Reading is more boring than watching TV.
→ Watching TV is more interesting than reading.

That book belongs to Nam.
→ That is Nam's book.

What is the age of Peter?
→ How old is Peter?

No one in our class is taller than Nam.
→ Nam is the tallest in our class.

Mr. Hong drives very carefully.
→ Mr. Hong is a very careful driver.

Does your father cycle to work?
→ Does your father get to work by bicycle?

Why don't we go to the movies tonight?
→ What about going to the movies tonight?

She doesn't have classes on Sunday.
→ She never has classes on Sunday.

How wide is BaDmh square?
→ What is the width of BaDmh square?

Reading is more boring than watching TV.
→ Watching TV is more interesting than reading.

C. half a kilo

B. else

1. ➔ Incorrect: Remove "for".
Corrected: It's important to sign the form.

2.➔ Incorrect: Remove "in".
Corrected: Peter broke his arm playing rugby.

3.➔ Correct (✓)

4.➔ Correct (✓)

5.➔ Correct (✓)

6.➔ Incorrect: Remove "to".
Corrected: The girl's parents wouldn't let her stay out so late.

7.➔ Incorrect: Remove "enough".
Corrected: The book is too difficult for children to understand.

8.➔ Incorrect: Remove "for".
Corrected: Police found the woman lying dead on the floor.

9.➔ Incorrect: Remove "them".
Corrected: Cars are always expensive to repair.

10.➔ Correct (✓)

1.D. spring

2.A. food

3.C. cushion

4.B. pizza

5.C. candle

6.A. stripe

7.D. survey

8.A. ‘suitable

9.C. bathe

10.B. handed

1.D. information

2.B. invite

3.A. woman

4.B. enter

5.C. again

6.D. begin

1.A. go to

2.A. in / of

3.B. must

4.D. is going to

5.C. well enough

6.B. yourselves

7.A. of

8.C. ought to

9.B. visited

10.D. go

11.D. reserved

12.B. dangerous

13.A. over / up

14.C. rises/ sets

15.C. doing

16.A. shouldn’t

17.B. for

18.B. should

19.C. cycling

20.B. have to

21.B. should

22.D. for – in

23.B. crowded

24.A. have to

25.B. has to

26.C. greeting

27.A. touch

28.A. custom

29.B. tradition

30.D. address

31.D. five-coloured

32.C. passed down

33.B. table manners

34.A. take off

35.A. comment

36.A. should

37.B. don’t have to

38.D. have to

39.C. mustn’t

40.A. shouldn’t