\(18+\left(-3+x\right)-\left(44-x\right)=55\)
\(\Rightarrow x=42.\)
\(8x-x=49\)
\(\Rightarrow x=7\)
8x-x=49
8x-1x=49
(8-1).x=49
7x=49
x=49:7=7
\(\Rightarrow18-3+x-44+x=55\)
\(\Rightarrow x+x=55-18+3+44\)
\(\Rightarrow2x=84\)
\(\Rightarrow x=42\)
Vậy \(x=42\)