a: \(\Leftrightarrow\sqrt{x^2-3x+8}=x+1\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-1\\x^2-3x+8=x^2+2x+1\end{matrix}\right.\Leftrightarrow x=\dfrac{7}{5}\)
b: =>|2x-5|=x+7
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-7\\\left(2x-5-x-7\right)\left(2x-5+x+7\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-7\\\left(x-12\right)\left(3x+2\right)=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{2}{3}\\x=12\end{matrix}\right.\)
c: =>4 căn 5x-1=20
=>căn 5x-1=5
=>5x-1=25
=>x=26/5
d: =>2x-5=x+4 và x+4>=0
=>x=9
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