a) A= | x- 4,1| + | x - 2/3 | - 9

b) B=| 2 và 1/5 - x| + | x - 1/5 | + 8 và 1/5

c) C=| x + 3 và 1/2| + |x| - 3 và 1/2

x=a / m ; y= b / m

-2345/2341 lớn hơn 497/-499

Exercise: Rewrite these sentences in the passive voice

1. They use coal to heat their house.

2. This well-known historical site will attract many people.

3. He will repair my bike.

4. Visitors will leave umbrellas and raincoats in the cloakroom.

5. They will ban advertisements on TV.

6. Many countries around the world will use solar energy in the future.

7. We will use wind and solar power to solve the problem of energy shortages.

8. Nuclear and hydro power will generate a great deal of energy in the future.

9. The government will launch a campaign for using renewable energy next month.

10. They will increase the tax on petrol next year.

C: x=4