\(\frac{3x}{2.5}+\frac{3x}{5.8}+\frac{3x}{8.11}+\frac{3x}{11.14}=\frac{1}{21}\)

=> \(x\left(\frac{3}{2.5}+\frac{3}{5.8}+\frac{3}{8.11}+\frac{3}{11.14}\right)=\frac{1}{21}\)

=> \(x\left(\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+\frac{1}{8}-\frac{1}{11}+\frac{1}{11}-\frac{1}{14}\right)=\frac{1}{21}\)

=> \(x\left(\frac{1}{2}-\frac{1}{14}\right)=\frac{1}{21}\)

=> \(x.\frac{3}{7}=21\)

=> x = 49 

Vậy x = 49

Xin lỗi bạn nhé x = 1/9 bước cuối mình ghi sót 

sai rồi bạn ơi

\(3^x+3^{x+1}=3^8.2+2.3^8.2017^0\)
\(3^x+3^x.3=3^8.2^2\)
\(3^x=3^8.2^2:3\)
\(3^x=3^7.2^2\)
 

3x+3x+1=38.2+2.38.201703x+3x+1=38.2+2.38.20170

a) \(x\left(5+3x\right)-\left(x+1\right)\left(3x-2\right)=12\)

\(5x+3x^2-3x^2+2x-3x+2=12\)

\(4x=10\)

\(x=\frac{5}{2}\)

vậy \(x=\frac{5}{2}\)

\(13x\left(x-8\right)-x+8=0\)

\(13x\left(x-8\right)-\left(x-8\right)=0\)

\(\left(13x-1\right)\left(x-8\right)=0\)

\(\Rightarrow\orbr{\begin{cases}13x-1=0\\x-8=0\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{1}{13}\\x=8\end{cases}}\)

 vậy \(\orbr{\begin{cases}x=\frac{1}{13}\\x=8\end{cases}}\)

\(3x=8x\)

\(=>x\in\text{ }\left\{0;1\right\}\)

X=0

Mk tin chac

chuc bn hoc gioi!

nhae@

bn$

@_____@

x chỉ có thể bằng 0 thôi bạn nhé

a,x-(20-3x)=x+7

=>x-20+3x=x+7

=>x-20+3x-x=7

=>x+3x-x=7+20

=>3x=27

=>x=27:3

=>x=9

bai toan lop 6 nay kho qua ?

mik mới học lớp 5 thôi!

<=> (3x+2)⁸ . [ 1 - (3x+2)¹⁰ ] = 0

TH1: 3x+2 = 0 <=> x = -2/3

TH2: 3x+2 = 1 => x = -1/3

TH3: 3x+2 = -1 => x = -1

ths bn

3x+8 = 3(x+2) +2 

=> 2 chia hết cho x+2 => x+2 =1;=> x =-1

                                      x+2 =2 => x =0

                                     x+2 =-1 => x =-3

                                    x+2 = -3 => x =-5

x( x + 3) + 3x + 8

\(x\left(x+3\right)+x+2x+8=0\)

\(x\left(x+4\right)+2\left(x+4\right)=0\)

\(\left(x+2\right).\left(x+4\right)=0\)

TH1:

\(x+2=0\)

\(x=0-2\)

\(x=-2\)

TH2: 

\(x+4=0\)

\(x=0-4\)

\(x=-4\)

Vậy \(x\in\left\{-2;-4\right\}\)