\(\left(1\right)7\sqrt{25x}=35\Leftrightarrow35\sqrt{x}=35\Leftrightarrow x=1\left(tm\right)\left(đk:x\ge0\right)\)
\(\left(2\right)\sqrt{\left(x-5\right)^2}=2x\)
\(\Leftrightarrow\left|x-5\right|=2x\)
\(\Leftrightarrow\left[{}\begin{matrix}x-5=2x\\x-5=-2x\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-5\\x=\dfrac{5}{3}\end{matrix}\right.\)
\(\left(3\right)\sqrt{\left(x-5\right)^2}=4x-2\)
\(\Leftrightarrow\left|x-5\right|=4x-2\)
\(\Leftrightarrow\left[{}\begin{matrix}x-5=4x-2\\x-5=-4x+2\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=\dfrac{7}{5}\end{matrix}\right.\)
\(\left(4\right)\sqrt{\left(2x+3\right)^2}+x=15\)
\(\Leftrightarrow\left|2x+3\right|=15-x\)
\(\Leftrightarrow\left[{}\begin{matrix}2x+3=15-x\\2x+3=-15+x\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-18\end{matrix}\right.\)
1: =>5 căn x=5
=>căn x=1
=>x=1
2: =>|x-5|=2x
\(\Leftrightarrow\left\{{}\begin{matrix}x>=0\\\left(2x-x+5\right)\left(2x+x-5\right)=0\end{matrix}\right.\Leftrightarrow x=\dfrac{5}{3}\)
3: =>|x-5|=4x-2
\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{1}{2}\\\left(4x-2-x+5\right)\left(4x-2+x-5\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{1}{2}\\\left(3x+3\right)\left(5x-7\right)=0\end{matrix}\right.\Leftrightarrow x=\dfrac{7}{5}\)
