Nếu x > 0
\(\Rightarrow\hept{\begin{cases}|2x-5|=2x-5\\|2x-15|=2x-15\end{cases}}\)
\(\Leftrightarrow2x-5+2x-15=10\)
\(\Leftrightarrow4x=30\)
\(\Leftrightarrow x=\frac{15}{2}\)
Nếu x < 0
\(\Rightarrow\hept{\begin{cases}|2x-5|=-2x+5\\|2x-15|=-2x+15\end{cases}}\)
\(\Leftrightarrow-2x+5-2x+15=10\)
\(\Leftrightarrow-4x=-10\)
\(\Leftrightarrow x=\frac{5}{2}\)
Vậy...
| \(\frac{5}{2}\) | \(\frac{15}{2}\) | ||||
| \(\left|2x-5\right|\) | \(5-2x\) | 0 | \(5-2x\) | | | \(2x-5\) |
| \(\left|2x-15\right|\) | \(15-2x\) | | | \(2x-15\) | 0 | \(2x-15\) |
| \(\left|2x-5\right|\)+\(\left|2x-15\right|\)=10 | 20-4x | | | -10 | | | 4x-10 |
\(\Rightarrow20-4x=10\) với x\(\ge\)\(\frac{5}{2}\)
\(\Rightarrow4x=10\)
\(\Rightarrow x=\frac{5}{2}\)(t/m)
\(\Rightarrow-10=10\) (loại) với \(\frac{5}{2}< x< \frac{15}{2}\)
\(\Rightarrow4x-10=10\)với x\(\le\frac{15}{2}\)
\(\Rightarrow4x=20\Rightarrow x=5\)
Vậy x=...........
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