Bài 3 :
\(\left|x-1\right|-10=2x+7\)
\(\Leftrightarrow\left|x-1\right|=2x+17\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1=2x+17\\x-1=-2x-17\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-18\\x=\frac{-16}{3}\end{matrix}\right.\)
Tìm GTNN :
\(B=\left|2x-4\right|+5\ge5\forall x\)
Dấu "=" \(\Leftrightarrow x=2\)