Tìm x: (8x-3)(3x+2)-(4x+7)(x+4)=(2x+1)(5x-1)-33

`(8x-3)(3x+2)-(4x+7)(x+4)=(2x+1)(5x-1)-33`

`<=>24x^{2}+16x-9x-6-4x^{2}-16x-7x-28=10x^{2}-2x+5x-1-33`

`<=>24x^{2}+7x-6-4x^{2}-23x-28=10x^{2}+3x-1-33`

`<=>20x^{2}-16x-34-10x^{2}-3x+1+33=0`

`<=>10x^{2}-19=0`

`<=>x(10x-19)=0`

`<=>`$\left[\begin{matrix} x=0\\ 10x-19=0\end{matrix}\right.$

`<=>`$\left[\begin{matrix} x=0\\ 10x=19\end{matrix}\right.$

`<=>`$\left[\begin{matrix} x=0\\ x=\dfrac{19}{10}\end{matrix}\right.$

`Vậy` `S={0;\frac{19}{10}}`

`@buiducthang25022009`