Tìm x,y € Z biết: a)xy+3x-y=-18 b)xy-x-y=-15

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điền từ hỏi thích hợp nha mn 1. .........................................................................................to the zoo ? - You can get there by bus. 2. .........................................................................................Phu Quoc Island? - You can get there by ship. 3. .........................................................................................the post office? - Go along that street. It's by the lake. 4. .........................................................................................the nearest bookshop? - Go straight ahead. It's on the right. 5. How .....................................................................................? - A motorbike rider hit him. 6. .........................................................................................live? - I live in a village. 7. What's .........................................................................................like? - I'ts beautiful. It's got a lot of parks. 8. ................................... New York like? -It's modern. It's got a lot of buildings. 9. ..................................................................? - There will be a robot. I'll use it to do the housework. 10. ...............................................................................? - I have got a stomachache. 11. ..................................................................free time? - I go camping and surf the Net. 12. . ..................................................................by plane? - 2 hours. 13. .................................................................. tomorrow? - It'll very cold and snowy. 14. . ..................................................................? - There will be a fridge. I'll use it to keep food fresh. 15. . ..................................................................? - You should use some eye drops 16. . ..................................................................? - You may get a burn 17. ..................................................................like? - I like Snow White. She's very beautiful. 18. . ..................................................................? - It'll be a large house. It's got a yard. 19. ..................................................................the cat? - Because it may scratch his face. 20. . ..................................................................your country? It's often hot. There is much rain.