5X = 16Y - 4
X = 3,2Y - 0,8
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6 * ( 3,2Y - 0,8 ) = 25Y + 1
19,2Y - 4,8 = 25Y + 1
5,8Y = - 5,8
Y = - 1
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X = - 3,2 - 0,8 = - 4
ОТВЕТ ( - 4 ; - 1 )
корень из 8=4*2(под знаком корня)=2 корня из 2.(т.е. после первой двойки-ставим знак корня а затем пишим вторую двойку.
Mr and Mrs Davis have a son. His name is Bobby, and it was his birthday a few days ago.
Last Sunday Bobby's grandfather came to visit them, and he brought Bobby a nice toy train. When he gave it to Bobby, he said: "I'm sorry, Bobby, but I forgot your birthday last Tuesday, so I give you this present then."
"Oh, that doesn't matter Grandpa," Bobby answered. "Thank you very much. It's just what I wanted."
"And how old are you now, Bobby?" his grandfather asked. Bobby knew the answer to that question. "I'm five, Grandpa," he said.
"That's good," the old man said. "You're a big boy now, Bobby. And what are you going to be when you're older?" Bobby knew the answer to that question, too. "I' m going to be six, Grandpa," he answered
Этот?
Скорей всего
tan(2y)-tan(y)