\(7-\left|2x+1\right|=x\)
\(\Rightarrow\left|2x+1\right|=7-x\)
\(\Rightarrow\left[{}\begin{matrix}2x+1=-7+x\\2x+1=7-x\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}2x-x=-7-1\\2x+x=7-1\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=-8\\3x=6\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=-8\\x=2\end{matrix}\right.\)
=>|2x+1|=7-x
=>x<=7 và (2x+1)^2=(7-x)^2=(x-7)^2
=>x<=7 và (2x+1-x+7)(2x+1+x-7)=0
=>x<=7 và (x+8)(3x-6)=0
=>x=2 hoặc x=-8
7−|2x+1|=x7−|2�+1|=�
⇒|2x+1|=7−x⇒|2�+1|=7−�
⇒[2x+1=−7+x2x+1=7−x⇒[2�+1=−7+�2�+1=7−�
⇒[2x−x=−7−12x+x=7−1⇒[2�−�=−7−12�+�=7−1
⇒[x=−83x=6⇒[�=−83�=6
⇒[x=−8x=2
