Bài `1 :`
$-2\cdot\left(2x-8\right)+3\cdot\left(4-2x\right)=-72-5\cdot\left(3x-7\right)$
`<=>` $-2\cdot2x-2\cdot-8+3\cdot\left(4-2x\right)=-72-5\cdot\left(3x-7\right)$
`<=>` $-4x+16+3\cdot\left(4-2x\right)=-72-5\cdot\left(3x-7\right)$
`<=>` $-4x+16+3\cdot4+3\cdot-2x=-72-5\cdot\left(3x-7\right)$
`<=>` $-4x+16+12+3\cdot-2x=-72-5\cdot\left(3x-7\right)$
`<=>` $\left(-4x-6x\right)+\left(16+12\right)=-72-5\cdot\left(3x-7\right)$
`<=>` $-10x+\left(16+12\right)=-72-5\cdot\left(3x-7\right)$
`<=>` $-10x+28=-72-5\cdot\left(3x-7\right)$
`<=>` $-10x+28=-72-\left(5\cdot3x+5\cdot-7\right)$
`<=>` $-10x+28=-72-\left(15x-35\right)$
`<=>` $-10x+28=-72-15x+35$
`<=>` $-10x+28=-15x+\left(-72+35\right)$
`<=>` $-10x+28=-15x-37$
`<=>` $−10x+28−28=−15x−37−28$
`<=>` $-10x+0=-15x-37-28$
`<=>` $-10x=-15x-37-28$
`<=>` $-10x=-15x-65$
`<=>` $-10x+15x=-15~x-65+15x$
`<=>` $5x=-15x-65+15x$
`<=>` $5x=-15x+15x-65$
`<=>` $5x=-65$
`<=>``\frac{5x}{5}=\frac{-65}{5}`
`<=>x=\frac{-65}{5}`
`<=>x=\frac{-13\cdot5}{1\cdot5}`
`<=> x=-13`
Bài `2 :`
`3|2x^2-7|=33`
`=>``|2x^2-7|=11`
`2x^2-7=11 ⇒ 2x²=18 ⇒ x²=9 ⇒ x=±3 (TM)`
`2x^2-7=-11⇒x^2=-4(KTM)`
`=>` $\left[ \begin{array}{l}x=3\\x=-3\end{array} \right.$
