\(\left(1-x\right)\left(5x+3\right)=\left(3x-7\right)\left(x-1\right)\)
\(\Rightarrow5x+3-5.x^2-3x=3.x^2-3x-7x+7\)
\(\Rightarrow5x-5.x^2-3x+3=3.x^2-3x-7x+7\)
\(\Rightarrow\)5x - 5x\(^2\) -3x - 3x\(^2\) +3x+7x = 7-3
\(\Rightarrow\) 12x - 5x\(^2-3x^2=4\)
\(\Rightarrow12x-8x^2=4\)
\(\Rightarrow4x\left(3-2x\right)=4\)
\(\Rightarrow3-2x=\frac{4}{4x}=\frac{1}{x}\)
...... làm tiếp nhé!