`~rai~`
\(a)\sqrt{2x-15}=3\quad(x\ge\dfrac{15}{2})\\\Leftrightarrow (\sqrt{2x-15})^2=3^2\\\Leftrightarrow 2x-15=9\\\Leftrightarrow 2x=24\\\Leftrightarrow x=12.\text{(thỏa mãn)}\\\text{Vậy x=12.}\\b)\sqrt{3x+4}=7\quad(x\ge-\dfrac{4}{3})\\\Leftrightarrow (\sqrt{3x+4})^2=7^2\\\Leftrightarrow 3x+4=49\\\Leftrightarrow 3x=45\\\Leftrightarrow x=15.\text{(thỏa mãn)}\\\text{Vậy x=15.}\\c)\sqrt{3x-2}=3\quad(x\ge\dfrac{2}{3})\\\Leftrightarrow (\sqrt{3x-2})^2=3^2\\\Leftrightarrow 3x-2=9\\\Leftrightarrow 3x=11\\\Leftrightarrow x=\dfrac{11}{3}.\text{(thỏa mãn)}\\\text{Vậy x=}\dfrac{11}{3}.\)
`\sqrt{2x-15}=3` `(x\ge15/2)`
`<=>2x-15=9`
`<=>2x=24`
`<=>x=12` (TM)
Vậy `S={12}`
$\\$
`\sqrt{3x+4}=7` `(x\ge-4/3)`
`<=>3x+4=49`
`<=>3x=45`
`<=>x=15` (TM)
Vậy `S={15}`
`\sqrt{3x-2}=3` `(x\ge2/3)`
`<=>3x-2=9`
`<=>3x=11`
`<=>x=11/3` (TM)
Vậy `S={11/3}`
Giải các bất phương trình sau và biểu diễn tập nghiệm trên trục số : a) 3x-2 < 4 b) 2-5x ≤ 17 .
Giúp mik ạ ............................
IV: Choose the right tense. 1. I saw/ was seeing the accident when I was waiting for the taxi. 2. What were you doing/ did you do when I phoned? 3. They didn't visit/ weren't visiting their friends last summer holiday. 4. It rained/ was raining heavily last July. 5. While people were talking to each other, he read/ was reading his book. 6. Chris was eating/ ate pizza every weekend last month. 7. While we were running/ run in the park, Mary fell over. 8. Did you find/ Were you finding your keys yesterday? 9. Who was she dancing/ did she dance with at the party last night? 10. They were watching/ watched football on TV all day. Mn giúp mk ik ạ Cảm ơn Pls
23 Có bao nhiêu quả dưa hấu trong hình? (50đ), giúp mình nanh nha
1. The water was too cold. We couldn’t swim in it. (TOO) -> _________________________________________________________________________________ 2. That’s the book. Everyone is reading it. (WHICH) -> _________________________________________________________________________________ 3. They didn’t have more people working on the job. They couldn’t get the job done quicker. (IF) -> _________________________________________________________________________________ 4. Her husband hated holidays so much. She decided to go on her own. (SINCE -> _________________________________________________________________________________ 5. She gave everyone a present. Then she left. (BEFORE) -> _________________________________________________________________________________ 6. We left a message with his neighbour. He would know we’d called. (SO THAT) -> _________________________________________________________________________________ 7. No one caught any fish. Everyone enjoyed the fishing trip. (THOUGH) -> _________________________________________________________________________________ 8. My grandfather gets older. He is more forgetful. (THE) -> ___________________________________________________________________________
tìm giá trị nhỏ nhất a) 3|2x+4|-5 b)Q=|x-7|+|x-9| tìm x a)10-2x bé hơn hoặc bằng -4 b)(6-3x)(2x+10)>0
Cho 2 tia đối nhau Ox và Oy trên cùng 1 nửa mp bờ đường thẳng xy vẽ 2 tia Oz Ot sao cho xOz = 78° yOt = 51° Tính yOz C.tỏ rằng Ot là tia pg của yOz
19. Sự nảy mầm là sự phát triển từ …………… thành cây con. Từ ngữ cần điền vào chỗ chấm là: A. Hạt B. Một bộ phận của cây mẹ C. Củ D. Lá 20. Biện pháp diệt côn trùng nào không có lợi cho đồng ruộng? A. Bắt sâu B. Phun thuốc trừ sâu C. Diệt bướm bằng vợt D. Phun dung dịch chế từ thảo dược
cuối cùng cx thi cúi kì xg gòii:> Vẽ bé mầm vui đi ạ;-; Hoặc vẽ j đó vui vui đi ạ ><
Làm giùm em bài 2 và 3 vs ạ Giải thik kĩ giùm em
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