4+x/5-x=-2/3

=> 3(4+x)=-2(5-x)

      12+3x=-10+2x

      12+10=2x-3x

            22=-1x

              x= 22: (-1)

              x=-22

Vậy x= -22

Đúng thì k cho mình nha!!!

=> 3.(4+x) = -2.(5-x)

=> 12+3x = 2x-10

=> 3x = 2x-10-12 = 2x-22

=> 22 = 2x-3x = -2x

=> x = 22 : (-1) = -22

Vậy x = -22

Tk mk nha

x/3 = -12/9

=> x/3 = -4/3

=> x = -4

vậy_

1.Ta có: \(\frac{x}{3}=-\frac{12}{9}\)

=> \(\frac{3x}{9}=-\frac{12}{9}\)

=> 3x = -12

=> x = -12 : 3

=> x = -4

\(\frac{4}{5}x-\frac{8}{5}=-\frac{1}{2}\)

=> \(\frac{4}{5}x=-\frac{1}{2}+\frac{8}{5}\)

=> \(\frac{4}{5}x=\frac{11}{10}\)

=> \(x=\frac{11}{10}:\frac{4}{5}\)

=> \(x=\frac{11}{8}\)

\(\frac{x}{3}=-\frac{5}{6}\)

\(\Rightarrow x\times6=3\times\left(-5\right)\)

\(\Rightarrow x\times6=-15\)

\(\Rightarrow x=-\frac{15}{6}\)

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

Vậy \(x=-\frac{5}{2}\)

Các bạn ơi giúp mình nhanh nha !

để \(\frac{x}{x+5}\)nguyên

=> x\(⋮\)x+5

ta có : x+5\(⋮\)x+5

=>(x)-(x+5)\(⋮\)x+5

=>-5\(⋮\)x+5

=>x+5\(\in\)Ư(-5)={1;-1;5;-5}

ta có bảng :

Vậy x\(\in\left\{-4;-6;0;-10\right\}\)

a) \(x\in\left\{-3;\pm2;\pm1;0\right\}\)

b) \(x\in\left\{\pm4;\pm3;\pm2;\pm1;0\right\}\)

Ta có:\(\left(x-1\right)\left(x-3\right)\left(x+5\right)\ge0\)

\(\Rightarrow\left(x^2-4x+3\right)\left(x+5\right)\ge0\).Ta có 2 trường hợp:

TH1:\(\hept{\begin{cases}x^2-4x+3\ge0\\x+5\ge0\end{cases}}\)\(\Rightarrow\hept{\begin{cases}x^2-4x+4\ge1\\x+5\ge0\end{cases}}\)\(\Rightarrow\hept{\begin{cases}\left(x-2\right)^2\ge1\\x+5\ge0\end{cases}}\).Ta lại có 2 trường hợp:

                               Với  \(\hept{\begin{cases}x-2\ge1\\x+5\ge0\end{cases}}\)\(\Rightarrow x\ge3\)

                             Với \(\hept{\begin{cases}x-2\le1\\x+5\ge0\end{cases}}\)\(\Rightarrow-5\le x\le3\Rightarrow x\in\left\{-5,-4,-3\right\}\)

TH2:\(\hept{\begin{cases}x^2-4x+3\le0\\x+5\le0\end{cases}}\)\(\Rightarrow\hept{\begin{cases}\left(x-2\right)^2\le1\\x+5\le0\end{cases}}\)\(\Rightarrow\hept{\begin{cases}x-2\le1\\x+5\le0\end{cases}}\)\(\Rightarrow x\le-5\)

Vậy....................

\(\frac{x-4}{y-5}=\frac{4}{5}\Rightarrow\left(x-4\right)5=\left(y-5\right)4\)

\(\Rightarrow x.5-4.5=y.4-5.4\)

\(\Rightarrow x.5-20=y.4-20\)

\(\Rightarrow x.5=y.4\)

\(\Rightarrow\frac{x}{y}=\frac{4}{5};x-y=-3\)

đến đây áp dụng theo bài toán hiệu-tỉ là OK!

X-4/y-5=4/5  

=> (x-4)5 = (y-5)4

 =>x.5-4.5=y.4 -5.4

 => x.5-20= y.4 - 20

=>x.5=y.4

=> x/y= 4/5;x-y=-3

dến đây áp dụng công thức tổng hiệu.

\(\frac{x-2}{27}+\frac{x-3}{26}+\frac{x-4}{25}+\frac{x-5}{24}+\frac{x-44}{5}=1\)

\(\Leftrightarrow\left(\frac{x-2}{27}-1\right)+\left(\frac{x-3}{26}-1\right)+\left(\frac{x-4}{25}-1\right)+\left(\frac{x-5}{24}-1\right)\)\(+\left(\frac{x-44}{5}+3\right)=1-1\)

\(\Leftrightarrow\frac{x-29}{27}+\frac{x-29}{26}+\frac{x-29}{25}+\frac{x-29}{24}\)\(+\frac{x-29}{5}=0\)

\(\Leftrightarrow\left(x-29\right)\left(\frac{1}{27}+\frac{1}{26}+\frac{1}{25}+\frac{1}{24}+\frac{1}{5}\right)=0\)

Mà \(\frac{1}{27}+\frac{1}{26}+\frac{1}{25}+\frac{1}{24}+\frac{1}{5}\ne0\)

=> x - 29 = 0

=> x = 29.