giải các phương trình sau 

1, \(\dfrac{3}{x-3}+\dfrac{4}{x+3}=\dfrac{3x-7}{x^2-9}\)

2, \(\dfrac{3}{x-4}-\dfrac{4}{x+4}=\dfrac{3x-4}{x^2-16}\)

3, \(\dfrac{5x^2-12}{x^2-1}+\dfrac{3}{x-1}=\dfrac{5x}{x+1}\)

giải các phương trình sau 

c, \(\dfrac{x+5}{x-2}=\dfrac{5\left(x+2\right)}{x^2-4}\)

d,\(\dfrac{5}{x-1}=\dfrac{4}{x+2}\)

giải các phương trinh sau 

a, \(\dfrac{2x+1}{x-2}=3\)

b, \(\dfrac{2x-3}{x+1}=\dfrac{1}{2}\)

1 , Lan and Mai saw  sharks, dolphins and turtles at Tri Nguyen aquarium.

dịch nghĩa 

20. I had already heard about the accident when he told me about it.

dịch nghĩa

7. I _bought__ a lot of gifts for my little sister. (buy)

8. Lan and Mai __saw__ sharks, dolphins and turtles at Tri Nguyen aquarium.

9. Trung __ate_ chicken and rice for dinner.

10. They _talked_ about their holiday in Hoi An. 

11. Phuong _returned_ to Hanoi yesterday. 

15. Hardly had the holiday begun when they left the town.

16. They had waited. out for an hour when it started to rain.

dịch nghĩa

1. I _stayed_ at home all weekend. 

2. Angela __went_ to the cinema last night. 

3. My friends __had__ a great time in Nha Trang last year. 

4. My vacation in Hue _was__ wonderful. 

5. Last summer I _visted__ Ngoc Son Temple in Ha Noi. 

6. My parents _were_ very tired after the trip. 

dịch nghĩa từng câu