Ta có :
$\dfrac{3+x}{5+y} = \dfrac{3}{5}$ $ĐKXĐ : y \neq -5$
$⇔15+5x=15+3y$
$⇔5x-3y=0$
Mà : $x+y=16$
$⇔5x+5y=80$
$⇒(5x+5y)-(5x-3y)=80$
$⇒8y=80$
$⇒y=10 ⇒ x= 6$
Vậy : $(x,y)=(6,10)$
Giải thích các bước giải:
$\dfrac{3 + x}{5 + y} = \dfrac{3}{5}$
$\to 5(3 + x) = 3(5 + y)$
$\to 5x + 15 = 3y + 15$
$\to 5x - 3y = 0$
Lại có: $x + y = 16$
$\to x = 6, y = 10$
Khi đang hoạt động mà bị chuột rút thì không nên
305. Take my advice and don’t drink so much whisky. If I ____________________________________________________________________ 306. I last went there when I was a child. I have __________________________________________________________________ 307. Hurry or you will late for the train. If you __________________________________________________________________ 308. “Did you go out with your brother last night ?” said John to me. John asked me ___________________________________________________________ 309. She last wrote to me 3 months ago. She hasn’t ______________________________________________________________ 310. It is very useful to speak English fluently. Speaking English ________________________________________________________ 311. “I’ll complete the work only if you pay me 10$ extra” said Tom. “Unless ________________________________________________________________ 312. The architect has drawn plans for an extension to the house. Plans __________________________________________________________________ 313. We didn’t go on holiday because we didn’t have enough money. If _____________________________________________________________________ 314. Unless he phones immediately, he won’t get any information. If _____________________________________________________________________ 315. The child will die if nobody sends for a doctor. Unless _________________________________________________________________
Mn giúp mik nha mik đng cần gấp cảm ơn ạ
Rút gọn: 1/2(x-2)(x-3) = 1/2xy - 16
Write a paragraph about 10 sentences to discribe your school
294. The film is more interesting than the one I last saw. The film I last saw was ____________________________________________________ 295. Lan used to walk pass the mosque in the past. Lan ___________________________________________________________________ 296. We spent a whole day looking for these old pictures. It took _________________________________________________________________ 297. Learning a foreign language is interesting. It _____________________________________________________________________ 298. Although Tom took a taxi, he was still late for the party. In spite of ______________________________________________________________ 299. They will build a new market near my house. A new market ___________________________________________________________ 300. I haven’t visited my parents for three months. I ______________________________________________________________________ 301. It’s very convenient to wear jeans at work. Wearing jeans ___________________________________________________________ 302. I haven’t seen her at this club before. This is _________________________________________________________________ 303. How much is this book ? What does ______________________________________________________________ 304. People built this cathedral nearly 200 years ago. This cathedral ___________________________________________________________
có mấy nội dung lao động của nghề điện ??
Tìm số hữu tỉ x biết rằng: x+7/2000 + x+6/2001 = x+5/2002 + x+4/2003
Trong 1 buổi lao động khối 8 gồm 120 học sinh chia thành 3 tốp : tốp thứ nhất trồng cây , tốp thứ 2 tưới cây , tốp 3 tưới cây vườn trường số học sinh tốp trồng cây gấp 3 lần số học sinh tốp tưới cây số học sinh của tốp lm vườn trường bằng 1/2 tổng học sinh của tốp trồng cây và tốp tười cây . Hỏi tốp trồng cây bao nhiêu học sinh ? LÀM CẢ GẢI THÍCH HỘ MIK NHA AI LM DC VOTE 5 SAO Ạ !!
Các bạn giải giúp mình với cảm ơn nhiều bài II nhé
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