\(3,5\times12+0,35:0,1\times3-35:10\times5\)

\(=3,5\times12+3,5\times3-3,5\times5\)

\(=3,5\times\left(12+3-5\right)\)

\(=3,5\times\left(15-5\right)\)

\(=3,5\times10\)

\(=35\)

Mai/intelligent/Kien

\(\rightarrow\)Mai is more intelligent than Kien.

\(Translate\): Mai thông minh hơn Kiên. 

\(\left(-2021\right)+\left(-999\right)+21+\left(-2001\right)\)

\(=\left[\left(-2021\right)+21\right]+\left[\left(-999\right)+\left(-2001\right)\right]\)

\(=-2000+\left(-3000\right)\)

\(=-5000\)

`45 : (3x - 4) = 3`

``\(\Rightarrow3x-4=45:3\)

\(\Rightarrow3x-4=15\)

\(\Rightarrow3x=15+4\)

\(\Rightarrow3x=19\)

\(\Rightarrow x=19:3\)

\(\Rightarrow x=\dfrac{19}{3}\)

Vậy \(x=\dfrac{19}{3}\)

`5(x+5) - 3(x-2) = 5^2 + 18`

`=> 5x + 25 -3x + 6 = 25 + 18`

`=> 5x - 3x = 25 + 18 - 6 - 25`

`=> 2x = 12`

`=> x = 12 : 2`

`=> x = 6`

Vậy `x = 6`

Rất xin lỗi em nhiều về bài làm sai sót của chị ở trên

\(5\left(x+5\right)-3\left(x-2\right)=5^2+18\)

\(\Rightarrow5x+25-3x-6=25+18\)

\(\Rightarrow5x-3x=25+18+6-25\)

\(\Rightarrow2x=24\)

\(\Rightarrow x=24:2\)

\(\Rightarrow x=12\)

Vậy `x = 12`

\(A=1+2+2^2+2^3+2^4+...+2^{19}+2^{20}\)

\(2A=2+2^2+2^3+2^4+2^5+...+2^{20}+2^{21}\)

\(2A-A=\left(2+2^2+2^3+2^4+2^5+...+2^{20}+2^{21}\right)-\left(1+2+2^2+2^3+2^{40}+...+2^{19}+2^{20}\right)\)

\(A=2^{21}-1\)

\(4,32\times1,5+43,2\times0,47+\dfrac{432}{100}\times2,8\)

\(=4,32\times1,5+4,32\times4,7+4,32\times2,8\)

\(=4,32\times\left(1,5+4,7+2,8\right)\)

\(=4,32\times9=38,88\)

`@`Phan Trung Khánh Không được cop Chat GPT nhé!

`-3752 - (29 - 3632) -51`

`= -3752 - 29 + 3632 - 51`

`= (-3752 + 3632) - (29 + 51)`

`= -120 - 80`

`=-200`