x-2y+4≤0
giúp mình với ạ

Cho hệ phương trình {2x+y=5m-1 ; x-2y=2 (m là tham số)
a) Giải hệ phương trình với m=1
b) Tìm m để hệ phương trình có nghiệm(x,y)thỏa mãn x\(^2\)-2y\(^2\)=1

Exercise 1: Underline the most suitable phrase in each sentence:
1. Is this a person / the person you told me about.
2. This is the only cinema / an only cinema in the area.
3. Philip has just bought the Thames barge / a Thames barge.
4. I’m going to the British Museum / British Museum this afternoon.
5. Are you going to church / the church on Sunday?
6. Do you have a milk jug / milk jug?
7. The Prime Minister / Prime Minister will give a speech this afternoon.
8. The computer / Computer has already changed our lives dramatically.
9. I haven’t been to an open-air theatre / open-air theatre before.
10. Here is a thousand pounds / the a thousand pounds I owe you.
11. I was under an impression / under the impression that you had left.
12. I have to go I’m in a hurry/ in hurry.
13. I managed to sell the old painting at a profit / at profit.
14. I think I prefer the other restaurant on the whole / on whole.
15. How many hours do you work, on average / on the average, every week?
16. I was in pain / in a pain after I twist my ankle.
17. Jack recovered from his accident and is now out of danger / out of the danger.
18. Excuse me, but you’re in the way / in a way.
19. Sue felt seasick on the cross- channel ferry / a cross- channel ferry.
20. The burglar hit me on my back of the neck / the back of my neck.