Если a²+2ab+b²/a²-b² =2a+2b, где |a| не равно |b|. Какова стоимость a-b
Срооочно!!!

Fill in is or are.

1. Be careful! Those scissors ... very sharp.

2. Maths ... John’s favourite subject at school.

3. The police ... investigating the crime.

4. These trousers ... too big for me.

5. The stairs in my house ... made of wood.

6. His new furniture ... very modern.

7. The weather ... going to be bad this weekend.

8. My advice ... that you get a new job.

9. His new clothes ... very fashionable.

10. The team ... all training hard for Saturday’s match.

11. The money in the jar ... for this week’s shopping.

12. My pyjamas ... not on my bed. Where ... they?

13. Mumps ... a childhood disease.

14. My luggage ... in the car already.

15. Your hair ... very long again.

16. Tom’s gloves ... made of soft leather.

17. The class all ... working on a project together.

18. Athletics ... my favourite sport.

19. My shoes ... too small for me now.

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