Tìm m để góc giữa 2 đường thẳng d1: (m+3)x-(m-1)y+m-3=0 d2: x+2y-5m-7=0 bằng 90 độ (AI BIẾT LÀM THÌ MỚI LÀM HỘ MÌNH NHỚ)

Hai địa điểm A và B cách nhau 33,8 km .lúc 7 giờ 30 phút người thứ nhất đi từ A đến B với vận tốc 10 km h lúc 8 giờ người thứ hai đi từ B đến A với vận tốc 14 km h. Hỏi: A)hai người gặp nhau lúc mấy giờ? B) chỗ gặp nhau cách từ điểm A bao nhiêu km

giúp zới !@#$%^&*()+_)(*&^%$#@!~!@#$%^&*(

In......... to sugar and milk , we need some eggs to make an apple pie (ADD) We ` d like .......our factory with modern mechines(EQUIPMENT) We should not eat too much .............food and sugar (FAT) These .....................like to stay in this hotel (VISITED) Water is a................ of oxygen and hydrogen (MIX) He always drives at a ................speed (MODERATION)

giup mik giai bai 7 voi dang gap ^^!

Exercise 13 1. A year has twelve months. -> There are ..................................................................................... 2. Lan is more intelligent than her sister. -> Lan’s sister isn’t ......................................................................... 3. He looks after the sick people. -> He takes ...................................................................................... 4. Do you enjoy listening to music? -> Are you interested......................................................................? 5. What is your mother’s job? -> What does................................................................................? 6. We have a two - month summer vacation. -> Our summer vacation lasts........................................................... 7. Will you please look after the house while we are away? -> Will you please take……………...............................................? 8. Vietnamese students have fewer vacations than American ones. -> American students....................................................................... 9. It takes me about two hours each day to do my homework. -> I spend.......................................................................................... 10. Hoa is a hard student. -> Hoa studies................................................................................... Exercise 14 1. What is Mai’s weight? -> How ………………………………….? 2. Why isn’t this TV working now? -> What’s …………………………………..? 3. Trung didn’t go to school last Saturday. -> Trung was ………………………………… 4. Christiano Ronaldo is a very good soccer player. -> Christiano Ronaldo plays ………………………………. 5. My brother runs faster than me -> I …………………………………………. Rewrite the sentences 1. She didn’t eat that food and they didn’t eat it, either. Neither she nor……………………………............ 2. Mr. Thanh couldn’t enjoy the meal because of the stomachache. The stomachache prevented……………….................…………..…..…….. 3. It isn’t important for you to finish the work today. You don’t……….…………………………....................... 4. The visitor spoke so quickly that I couldn’t understand what he said. The visitor spoke too………….………………….……………………….……….. 5. Lan didn’t go to school yesterday because of her sickness. Because Lan…………………………………………………..…………………… 6. Nhung will be fifteen next week.  It is Nhung’s……………..……….……………………………..... 7. Walking in the rain gives my brother pleasure. My brother enjoys…………………….…………………………….…………….. 8. I get to work in half an hour. It takes……………………………...……………………………. 9. Keeping the environment clean is very important. It’s……………….………………………….. 10. The water was so cold that the children couldn’t swim in it. The water was not…………….……………………………………….…… 11. Tam doesn’t type as fast as she used to. Tam used…………………………..…............………………….. 12. “ Please turn down the radio for me,” said his father. His father asked…………............…………………… 13. Nhung will be fifteen next week.  It is Nhung’s……………………….……….............…………………… 14. How long is it since you used the car? When ………………………….………….............………………..? 15. They will show the time machine to the public when they finish it. The time machine………………................................................................................….. 16. He was delighted to receive his aunt’s letter. He was delighted that……...........……………………………. 17. Vinh keeps forgetting his homework. Vinh is………………………………...........…….………………….

giúp mik với mn ơi tính nhanh: A=5/1.6 -5/6.11 -5/11.16 -...-5/2006.2011 M=5^2018/5^2017 +1 N=5^2017 +1/5^2016+1 giải các bước giải đầy đủ và chính xá cho 5 vote

máy biến áp 1 pha co U1=110V , U2 = 12V , số vòng dây N1=220 vòng a) Hãy xác định vòng dây của N2 b) Máy biến áp trên là tăng áp hay giảm áp ? tại sao c) Khi điện áp U1=220V . Nếu ko điều chỉnh số vòng dây thì diện áp thứ cấp (U2) bằng bao nhiêu Mọi người giúp mk vơi ạ

CM câu tục ngữ gần mực thì đen gần đèn thì rạng Mn vt thộ mik trong xã hội,trong học tập thui nha

x^2+(m-1)x+5m-6=0 tìm m để phương trình có 2 nghiệm x1;x2 thỏa mãn 4X1+3X2=1