150-x=125+7

           150-x=132

                 x=150-132

                 x=18

trình độ bạn mà đặt câu này à? dễ quá

1/125 * x + 7/8 = 2

1/125 * x          = 2-7/8

1/125 * x          = 9/8

            x           = 1/125:9/8

            x           = 8/1125

5

4.2x – 3 = 125

4.2x = 125 + 3

4.2x = 128

2x = 128 : 4

2x = 32

2x = 25

x = 5

Vậy x = 5

\(\Leftrightarrow\left[{}\begin{matrix}5x-4=x+2\\4-5x=x+2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}4x=6\\6x=2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

|5x-4|=|x+2|

TH1: 5x-4=x+2⇒4x=6⇒x=3/2

TH2: 5x-4=-x-2⇒ 6x=2⇒x=1/3

Vậy ....

\(\left|5x-4\right|=\left|x+2\right|\)

\(\Rightarrow\left[{}\begin{matrix}5x-4=x+2\\5x-4=-x-2\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}5x-x=4+2\\5x+x=4-2\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}4x=6\\6x=2\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

Vậy \(x=\dfrac{3}{2}\) hoặc \(x=\dfrac{1}{3}\)

\(5x=7y\Rightarrow5.3y=7y\left(x=3y\right)\Rightarrow\)\(15y=7y\Rightarrow15y-7y=0\)\(\Rightarrow8y=0\Rightarrow y=0\Rightarrow x=0\)

\(\left(6+5x\right)^{50}=36^{25}\)

\(\left(6+5x\right)^{50}=6^{50}\)

\(\Rightarrow6+5x=6\)

\(\Rightarrow5x=0\)

\(\Rightarrow x=0\)

vay \(x=0\)

(6+5x)⁵⁰=36²⁵

=> [(6+5x)² ]²⁵=36²⁵

=> (6+5x)²=36

=> (6+5x)²=6²

=> 6+5x=6

=> 5x=0

=> x=0

\(\left(6+5x\right)^{50}=36^{25}\)

\(\left(6+5x\right)^{50}=\left(6^2\right)^{25}\)

\(\left(6+5x\right)^{50}=6^{50}\)

=> \(6+5x=6\)

      \(5x=0\)

       \(x=0\)

\(\Leftrightarrow x\left(y+5\right)=5y+36\)

\(\Leftrightarrow x=\dfrac{5y+36}{y+5}=\dfrac{5\left(y+5\right)+11}{y+5}=5+\dfrac{11}{y+5}\left(y\ne-5\right)\) (1)

x nguyên khi \(11⋮\left(y+5\right)\)

\(\Rightarrow\left(y+5\right)=\left\{-11;-1;1;11\right\}\)

\(\Rightarrow y=\left\{-16;-6;-4;6\right\}\) Lần lượt thay các giá trị của y vào (1) để tìm các giá trị tương ứng của x