a/ \(\left|x-1,5\right|=4,5\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1,5=4,5\\x-1,5=-4,5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=6\\x=-3\end{matrix}\right.\)
Vậy ...........
b/ \(\left|x-3\right|+\left|x-4\right|=3x\)
\(\Leftrightarrow x-3+x-4=3x\)
\(\Leftrightarrow2x-5=3x\)
\(\Leftrightarrow5=2x+3x\)
\(\Leftrightarrow5x=5\)
\(\Leftrightarrow x=1\)
Vậy ..
\(a)\left|x-1,5\right|=4,5\)
\(\Rightarrow\left[{}\begin{matrix}x-1,5=4,5\\x-1,5=-4,5\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=4,5+1,5\\x=-4,5+1,5\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=6\\x=-3\end{matrix}\right.\)
\(b)\left|x-3\right|+\left|x-4\right|=3x\)
\(\Leftrightarrow x-3+x-4=3x\)
\(\Leftrightarrow2x-5=3x\)
\(\Leftrightarrow5=2x+3x\)
\(\Leftrightarrow5x=5\)
\(\Rightarrow x=5:5\)
\(\Rightarrow x=1\)
