Cho tam giác MNP cân tại P (góc P <90 ĐỘ) ,vẽ MA vuông PN tại A, NC vuông PM tại C. Chứng minh: a) PC=PA,CA// MN b) Gọi I là giao điểm của MA và NC. Chứng minh:tam giác IMN cân. c) Tia PI cắt MN tại K. Chứng minh K là trung điểm của MN.

giúp mình vs, câu 1 a rồi câu nào đs cx đc

Tìm x thuộc z a) (x+7)×(x-9) =0 b) -13 × |x|=-26

Bài 1: Lập phưng trình TQ và TS của đường thẳng đi qua điểm M và có vtpt á biết: a M(k-1): a-(2:1) b. M(04): n=(-1:3) Bài 2: Lập PTTS và PTTQ của đường tháng đi qua điểm M và có vtcp u biết: a. M(t-2): u- (L0) b. M(S.3): u=(-3:1) Bài 3: Lập phưng trinh đường thắng đi qua 2 diểm A và B trong các trường hợp sau: b. A(42). B(-L-2) a A(-k1), B(2:1) Bài 4: Lập phương trinh đường trung trực của doạn thẳng AB biết: a A(l:1), B(-3.1) b, A(3,4), B(L-6) Bài 5: Lập phương trìinh đường thắng (d) biết: a di qua điểm M(2:-1) và có hệ số góc k = 2 b, đi qua điểm M(0;4) và có hệ số góc k= c, di qua điểm M(-3:-1) và tạo với hướng dương trục Ox góc 45. d, di qua điểm M(3:4) và tạo với hưởng đương trục Ox góc 60. Bài 6: Chuyển (d) về dạng tham số biết (d) có phương trình tổng quát: a. 2x - 3y = 0;

Hãy tính tổng các số nguyên x thỏa mãn -2016<_ x _<2018

Cho 1,28 gam mot kim loai M hoa tri 2 tac dung vua du voi 0,448 lit khi cl2 . Xac dinh ten kim loai M va khoi luong muoi tao thanh

giúp em với phần a nhé . Đang cần gấp

* Finish each of the following sentences in such a way that it means exactly the same as the sentences printed before it. 1. The trains couldn’t run because of the snow. ⇒ The snow .. 2. I didn’t arrive in time to see her. ⇒ I wasn’t early ..... 3. I’m sorry I was rude to you yesterday. ⇒ I apologize ..... 4. He didn’t hurry, so he missed the train. ⇒ If ...... 5. Janet is the best tennis- player in the club. ⇒ No one ....... 6. I haven’t seen that man here before. ⇒ It’s ......... 7. The furniture was so expensive that I didn’t buy it. ⇒ The furniture was too ......... 8. The robbers made the bank manager hand over the money. ⇒ The bank manger ......... 9. He learned to drive when he was 18. ⇒ He has ................................................................................................ 10. She had never been unhappy before. ⇒ She was unhappier ................... 11. It was so late that nothing could be done. ⇒ It was too .......... 12. I asked the hotel porter to wake me at 8 o’clock the following morning. ⇒ “ Please ......... 13. They’ll have to change the date of the meeting again. ⇒ The date ...... 14. The garage is going to repair the car for us next week. ⇒ We are going ............ 15. The bus takes longer than the train. ⇒ The train .............. 16. John has not had his hair cut for over six months. ⇒ It’s ............ 17. Maria says she’ll like to have been put in a high class. ⇒ Maria wishes ....... 18. Would you like me to finish the work tonight? ⇒ I’ll .... 19. You may get hungry on the train, so take some sandwiches. ⇒ In ..... 20. My husband didn’t leave the car keys, so I couldn’t pick him up at the station. ⇒ If my husband .............. 21. “I don’t think John will come,” said Bill. ⇒ Bill doubted ..... 22. The postman was bitten by our dog. ⇒ Our dog .......... 23. We couldn’t drive because of the fog. ⇒ The fog prevented ........ 24. Although his leg was broken he managed to get out of the car. ⇒ In spite .. 25. The cake was so hard that I could not eat it. ⇒ It was ... 26. We didn’t go because it rained. ⇒ If it hadn’t ... 27. I can’t cook as well as my mother does. ⇒ My mother ......... 28. I don’t suppose you have change for a pound, do you? ⇒ Do you happen ........ 29. He failed to win the race. ⇒ He didn’t ..... 30. Mary rang hours and hours ago. ⇒ It’s hours ...... 31. I’m sorry that I didn’t finish my homework last night. ⇒ I wish .......... 32. She asked John how he liked her new dress. ⇒ “How....... 33. A train leaves at eight o’clock every morning. ⇒ There is ............ 34. Nobody can deny that she has a beautiful voice. ⇒ It ...... 35. I would like you to help me to put the chairs away. ⇒ Do you mind ......... 36. The child will die if nobody sends for a doctor. ⇒Unless ....... 37. He would prefer you to pay him immediately. ⇒ He’d rather ............ 38. The water was so cold that the children could not swim in it. ⇒ The water was not ........ 39. Somebody repaired her car yesterday. ⇒ She .... 40. You must see the manger tomorrow morning. ⇒ You’ve ....... 41. There was never any answer when we rang. ⇒ Every ......... 42. That’s an insulting name to use for him. ⇒ Don’t call ........ 43. John asked if it was the blue one or the green she wanted. ⇒ “Which .... 44. She liked Paris very little, and Rome less. ⇒ She thought Rome ....... 45. I can meet you if you arrive before eleven. ⇒So ..... 46. They will catch all the prisoners again by tonight. ⇒ All the prisoners ........ 47. I’ve warned you not to go near that dog. ⇒ I’ve warned you about ..... 48. No, please don’t tell him. ⇒ I’d rather ......... 49. Why don’t you ask her yourself? ⇒ I suggest ......... 50. An up- to- dated visa is necessary for Andorra. ⇒ You’ll .....

(X-2)(y+1)=23 tìm x , y thuộc Z

cho tam giác ABC , vuông tại B,kẻ AH vuông với BC,biết AB = 3cm,BC = 4cm,AH = 2.4cm. Tính độ dài các đoạn thẳng AC, BH , CH (ai giúp mik với )