Giair phương trình sau:

1. (x - 3) (x + 4) = (2 - x) (1 - x)

2. \(\frac{2x}{15}\) - \(\frac{15-2x}{10}\) = \(\frac{7}{6}\)

3. \(\frac{x}{15}\) + \(\frac{x+1}{16}\) + \(\frac{x+2}{17}\) + \(\frac{x+3}{18}\) + \(\frac{x+4}{19}\) = 5

4. \(\frac{x+1}{11}\) + \(\frac{2x-5}{15}\) = \(\frac{3x-47}{17}\) - \(\frac{4x-59}{19}\)

5. x² + 9x + 20 = 0

6. x³ + 2x - 3 = 0

III. Rewrite the sentences below so that their meaning stay the same.
1. I'll call the police ì you don't leave me alone.

Unless.............................................................

2. You can't visit Moscow unless you get a visa.

If you..................................................................

3. Unless he phones right now, he won't get any ìnormation.

If.............................................................................

IV. Rewrite the sentences: (TYPE I)

1. Work hard and you will pass the exam.\(\rightarrow\) If...........

2. Hurry up or you'll be late for class.\(\rightarrow\)If you...........

3. Stop borrowing money , or you'll be in trouble.\(\rightarrow\)If..........

I. Combine each ò the following pairs of sentences into one sentence using so as/in order where necessary

1. Mary prepares her lesson carefully. She wants to get high marks in class.

2. The thief changed his address all the time. He didn't want to be found by the police.

3.They did their job well. They hoped to get a higher salary.

4. You should walk slowly. You can be followed by your sister.

5. I am studying hard. I want to keep pace with my classmates.

6. They are climbing higher. They want to get a better view.

7. He worked late last night. He wanted to be free to go away tomorrow.

8. Put the milk in the fridge. We want to make sure it won't spoil.

I. Use 'Would/Do you mind if...?' to make the following sentences more polite

1. Could I have a cup of tea? \(\Rightarrow\)Would...............

2. Can I use your headphone?\(\Rightarrow\)Do ..................

3. Shall I carry your luggage?\(\Rightarrow\)Would..............

4. Could I borrow your newspaper?\(\Rightarrow\)Do...............

5. Shall I drive?\(\Rightarrow\)Would............

6. Shall I sit here?\(\Rightarrow\)Do..............