=>45-|-2-x|=20
=>|-2-x|=45-20
=>|-2-x|=25
TH1:-2-x=25
=>x=-2-25
=>x=-27
TH2:-2-x=-25
=>x=-2-(-25)
=>x=23
Vậy x thuộc {-27;23}
Tk mik nha
45 - | 27 - ( - 25 ) - x | = 20
| 27 + 25 - x | = 45 - 20
| 50 - x | = 25
=> \(\orbr{\begin{cases}50-x=25\\50-x=-25\end{cases}}\) => \(\orbr{\begin{cases}x=50-25=25\\x=50-\left(-25\right)=75\end{cases}}\)
Vậy x \(\in\){ 25 ; 75 }