Lập bảng xét dấu :
| x | \(\frac{-5}{2}\) | \(\frac{1}{3}\) | |||
| 2x+5 | - | 0 | + | \(|\) | + |
| 1-3x | + | \(|\) | + | 0 | - |
+) Nếu \(x\le\frac{-5}{3}\) thì \(|2x+5|=-2x-5\)
\(|1-3x|=1-3x\)
\(pt\Leftrightarrow-2x-5=1-3x\)
\(\Leftrightarrow-2x+3x=1+5\)
\(\Leftrightarrow x=6\)( loại )
+) Nếu \(\frac{-5}{2}< x< \frac{1}{3}\) thì \(|2x+5|=2x+5\)
\(|1-3x|=1-3x\)
\(pt\Leftrightarrow2x+5=1-3x\)
\(\Leftrightarrow2x+3x=1-5\)
\(\Leftrightarrow5x=-4\)
\(\Leftrightarrow x=\frac{-4}{5}\left(tm\right)\)
+) Nếu \(x\ge\frac{1}{3}\) thì \(|2x+5|=2x+5\)
\(|1-3x|=3x-1\)
\(pt\Leftrightarrow2x+5=3x-1\)
\(\Leftrightarrow2x-3x=-1-5\)
\(\Leftrightarrow-x=-6\)
\(\Leftrightarrow x=6\left(tm\right)\)
Vậy ....