\(a)\) \(\left|x\right|=\left|x+2\right|=3\)
\(\text{Trường hợp 1:}\)
\(\Leftrightarrow x+x+2=3\)
\(\Leftrightarrow2x=1\)
\(\Leftrightarrow x=\frac{1}{2}\)
\(\text{Trường hợp 2:}\)
\(\Leftrightarrow-x-x-2=3\)
\(\Leftrightarrow-2x=5\)
\(\Leftrightarrow x=-\frac{5}{2}\)
\(b)\) \([\frac{12}{25}.\left(0,75+\frac{7}{4}\right)-1].x=[\frac{7}{5}-\frac{3}{25}.\left(10,6-\frac{3}{5}\right)]\)
\(\Leftrightarrow[\frac{12}{25}.2,5-1].x=[\frac{7}{5}-\frac{3}{25}.10]\)
\(\Leftrightarrow[1,2-1].x=[\frac{7}{5}-2]\)
\(\Leftrightarrow0,2.x=-\frac{3}{5}\)
\(\Leftrightarrow x=-\frac{3}{5}:0,2\)
\(\Leftrightarrow x-3\)
