(8x - 3)(3x - 2) - (4x + 7)(x + 4) = (2x + 1)(5x - 1)
=> 24x2 - 25x + 6 - 4x2 - 23x - 28 = 10x2 + 3x - 1
=> 10x2 - 51x - 21 = 0
Thua
\((8x-3).(3x+2)-(4x+7).(x+4)= (2x+1).(5x-1)-33\)
\(\Leftrightarrow24x^2+16x-9x-6-\left(4x^2+16x+7x+28\right)=10x^2-2x+5x-1-33\)
\(\Leftrightarrow24x^2+16x-9x-6-4x^2-16x-7x-28-10x^2+2x-5x+1+33=0\)
\(\Leftrightarrow10x^2-19x=0\)
\(\Leftrightarrow x.\left(10x-19\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\10x-19=0\end{matrix}\right.\)
\(\Leftrightarrow10x=19\)
\(\Leftrightarrow x=\dfrac{19}{10}\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{19}{10}\end{matrix}\right.\)
