Giá trị x = -4 là nghiệm của phân thức nào?

hai người xuất phát cùng một lúc từ 2 điểm a và b cách nhau 60 km .người thứ nhất đi xe máy với vận tốc v1=30km/h . người thứ 2 đi xe đạp tói b với vận tốc v2=10km/h .coi chuyển động của hai xe là đều . a, hỏi sau bao lâu 2 người gặp nhau? xác định chỗ gặp đó? b,hỏi sau bao lâu 2 người cách nhau 20 km

Mà kể questions for the underlined words/ phrases.

TÌM X x:3+x:4=21. X BẰNG BAO NHIÊU

Mọi người giúp với ạ:(( bài 9.15 phần b mình ra 60m còn 9.16 mình ra 0.25m không hiểu vì sao mình sai, giúp mình với cảm ơn mọi người trước

Một hình tam giác vuong co tong hai canh goc vuong la 88 m va canh goc vuong nay bang 0,6 lan canh goc vuong kia . Tren thua ruộng nay nguoi ta trong lua , trung binh cu 100 m vuong thu được 70 kg Thoc . Hoi tren ca thua ruộng , nguoi ta thu hoạch đuoc bao nhieu ta Thoc ?

Nguyên nhân tính chất của cuộc chiến tranh thế giới thứ hai điểm giống và khác nhau trong nguyên nhân dẫn tới chiến tranh thế giới thứ nhất và chiến tranh thế giới thứ 2.

Mọi người giải nhanh giúp em vs ạ.Em cảm ơn trước

1. Every year thousands of people _____ in their homes. A. kill B. is killed C. will be killed D. are killed 2. Coming into the room, he saw Mary where he _____ her. A. leaves B. left C. was leaving D. had left 3. I have searched everywhere for the pen I _____ yesterday. A. loosed B. lost C. lose D. losed 4. While I was walking to school, I _____ an accident. A. was seeing B. see C. seen D. saw 5. David ... the TV set at the moment. A. was repairing B has repaired C. is repairing D. has been repairing 6. He _____ his homework for 2 hours. A. have did B. has do C. has done D. did 7. He _____ for London two years ago and I _____ him since. A. leaved/ haven't seen B. left/ didn't see C. leave/ haven't seen D. left/ haven't seen 8. When the teacher came in, we stopped _____. A. to talk B. at talking C. talking D. talk 9. How long ago _____? A. has this house built B. was this house built C. this house built D. this house was built 10. I want you _____ me alone. A. leave B. leaving C. left D. to leave 11. People in New Zealand speak _____. A. French B. Spanish C. England D. English 12. He is trying to give up _____. A. smoking B. smoke C. smokes D. smoked 13. We are tired of _____ for the weather to clear. A. wait B. waiting C. to wait D. to waiting 14. My father is fond of _____. A. finishing B. fished C. fishes D. to fish 15. My brother hates _____ early. A. to get up B. getting C. to get D. getting up 16. She'd love _____ to the party with me. A. going B. to going C. goes D. to go 17. It is likely that life _____better in the future. A. to be B. is C. will be D. must 18. I'd rather _____to the cinema tonight. A. don't go B. not to go C. not going D. not go 19. Are you ready _____ the exam? A. for B. on C. to D. with 20. Elephants in this zoo _____ twice a day. A. are feed B. are feeding C. are fed D. is fed 21. That church _____by a fire in 1950. A. destroyed B. was destroyed C. was destroying D. has been destroyed 22. He _____ since we left school. A. wasn't seen B. didn't see C. hasn't been seen D. haven't been seen 23. A new school _____ in the city at present. A. is built B. is building C. is being built D. be built 24. My TV _____ has broken down twice. A. I bought last month B. that I bought last month C. which I bought it last month D. which I bought last month 25. My father bought a motorbike _____ costs two thousand dollars. A. which B. of which C. who D. whose 26. Ann _____ children learn very well, is our math teacher. A. who B. whose C. which D. that 27. This is the shop _____ I often buy my books. A. which B. that C. where D. when 28. Dalat, _____every visitor would like to spend their holiday, is a famous resort. A. where B. which C. that D. whose 29. The story is very _____. A. interest B. interesting C. interested D. interests 30. Children will need _____ education A. well B. better C. kind D. quickly 31. He used to drive _____ than he does now. A. careful B. more careful C more carefully D. carefully 32. Isaac Newton, _____ theory of gravitation is well-known throughout the world, is a great English scientist. A. who B. which C. that D. whose 33. A man whose _____ is in physics is a physicist. A. interest B. interesting C. interested D. fame 34. A man will be different _____ he is today. A. to B. in C. from D. as 35. English is by far the most widely _____. A. using B. used C. to use D. use 36. James Watt, whose___of the steam engine made him famous, was a Scottish scientist. A. invent B. inventor C. invention D. inventing 37. Ann speaks good English but Nam speaks it _____. A. well B. good C. better D. worse 38. Mary opened her book _____. A. care B. careful C. carefully D. careless 39. Would you like to go _____ with us this afternoon? A. to swim B. swimming C. a swim D. to swimming 40. I always wanted to be a great _____. A. science B. scientific C. scientist D. invention

Một cano đi xuôi dòng 48km rồi đi ngược dòng 22km. Biết rằng thời gian đi xuôi dòng lớn hơn thời gian đi ngược dòng 1 giờ và vận tốc đi xuôi lớn hơn vận tốc đi ngược 5km/h. Tính vận tốc cano lúc đi ngược dòng.