Вопрос школьника по предмету Физика
2х+у=7 4х-у=5 срочно
Ответ учителя по предмету Физика
Нужно сложить два этих вырожения
2х + 4х
у — у
7 + 5
6х = 12
х = 2
Подставляем полученный х в любое из двух выражений
4*2 — х = 5
8 — х = 5
x = 3
Ответ: х = 3, у = 2
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2)подпишите детали строения майского жука
The trip was not long. A few minutes later the magic plane was under a big old tree. Sarah was in the middle of the Wild Wood. She didn’t know where to go. «How can I get out of here?» she asked. «Can’t you find the road?» she suddenly heard a voice. She looked up and down, but couldn’t see anybody. There was just an ugly old tree near to where she stood. Then she heard the voice again. » Speak up! I can’t hear you! Don’t they teach you to speak English at school?» Sarah understood that the tree was talking to her. «Please, sit,» said Sarah. «I’m looking for some magic mustard seeds.» «The Vinegar Witch may have some, but I’m not sure», said the tree. «The road to the Witch’s castle is to the left of the road leading to the magic airport.» «Could you repeat that, please?» said Sarah. «That was very difficult to remember.» «Certainly not,» said the tree. «You, young people, must learn to work without help. Well, hurry up! And he shook his leaves sadly. Sarah went straight ahead. It was difficult to walk because it was dark. She wanted to take a bus , but there were no buses in the Wild Wood. So she had to go on foot. It was a long way. By the time she saw the Witch’s house it was already morning. She went up to the castle and saw that the key was in the door. She opened it and went in.» Come up here!» she heard a voice from upstairs. She went up and there she saw a large room. In the middle of this room there was a fire burning. In front of the fire there were two armchairs, and in one of them was an ugly old witch. Her friendly black cat, Midnight, was in the other.Once upon a time there was Spice Country.In the capital of the contry in its main square there was the Pepperpot Palace where Queen Salt and her favourite son Prince Pepper was vere rich. He had a lot of food but he liked mustard very much.He couldn’t live without mustard at all.In a poor little house which stood on the bank of the river near the bridge there lived a little girl, Sarah Sweet by name.She was the Prince’s friend.One day she went to visit Prince Pepper.She found him in bed as he was ill. «He is very ill,» said the doctor, «He can’t eat food without mustard in the shops.»
«No mustard?» said Sarah, «I don’t believe it.There is a lot of mustard in our Spice Country.»
«But it is not the right kind,» said the Queen. «It must be magic mustard.And someone has stolen all the Prince’s magic mustard seeds.We have told the police, but they can’t find the seeds. We think Vinegar Witch has done it, but she won’t talk to anyone but sweet, young girls.»
Suddenly the doctor looked at Sarah. «Why,» he said, «You’re a sweet, young girls. Will you help us?»
«Of course I will,» said Sarah. «But where does the Witch live? How can I get there?»
«She lives with her cat Midnight in a castke which is in the mountains,» answered the Queen. » You can get there by plane or by train but you’ll have to go on foot too.First find the magic road to the mountains.»
«I’m sure I’ll find it. Goodbye, everyone!» said Sarah and left the palace.
Sarah was sure she could get to the Witch by plane.The main thing was to find the magic airport.Suddenly she saw main thing was to find the magic airport.Suddenly she saw a taxi. «Taxi! Taxi!» cried Sarah. » Let’s go fast! I’m in a hurry!»
«Where to?» asked the drive, when he opened the door and asked Sarah to get in.
«To the airpkrt,» was the answer.
It took them 10 minutes ti get there.Sarah bought a ticket.She had no luggage, so very soon she wad ob the plane in the blue sky.