\(-2x+3.\left\{12-2.\left[3x-\left(20+2x\right)-4x+1\right]\right\}=45\)
\(\Leftrightarrow-2x+3.\left\{12-2\left[3x-20-2x-4x+1\right]\right\}=45\)
\(\Leftrightarrow-2x+3.\left\{12-2.\left[-3x-19\right]\right\}=45\)
\(\Leftrightarrow-2x+3.\left\{12+6x+38\right\}=45\)
\(\Leftrightarrow-2x+36+18x+114=45\)
\(\Leftrightarrow16x+150=45\Leftrightarrow16x=-105\Leftrightarrow x=\frac{-105}{16}\)
mình giúp rùi đó nhớ k mk nhé ....
= -2x + 3[12-2(3x-20-2x-4x+1)]=45
= -2x +3[12-2(-3x-19)]=45
= -2x+3(12+6x+38)=45
= -2x+3(6x+50)=45
=-2x+18x+150=45
=16x=-105
=>x=-105/16
