1.\(\left(\dfrac{1}{3}-x\right)^2=\dfrac{9}{25}\Leftrightarrow\left[{}\begin{matrix}\dfrac{1}{3}-x=\dfrac{3}{5}\\\dfrac{1}{3}-x=-\dfrac{3}{5}\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{4}{15}\\x=\dfrac{14}{15}\end{matrix}\right.\)
2.\(\left(5-x\right)^2=25\Leftrightarrow\left[{}\begin{matrix}5-x=5\\5-x=-5\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=10\end{matrix}\right.\)