1) \(x^3-25x=0\)

\(\Leftrightarrow x\cdot\left(x^2-25\right)=0\)

\(\Rightarrow x\cdot\left(x-5\right)\cdot\left(x+5\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x-5=0\\x+5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=5\\x=-5\end{matrix}\right.\)

2) \(2x\left(x-1\right)-3x+3=0\)

\(\Leftrightarrow2x\left(x-1\right)-3\left(x-1\right)=0\)

\(\Leftrightarrow\left(2x-3\right)\left(x-1\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}2x-3=0\\x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1,5\\x=1\end{matrix}\right.\)

3) \(x^2-36+\left(x^2-12x+36\right)=0\)

\(\Leftrightarrow x^2-36+\left(x-6\right)^2=0\)

\(\Leftrightarrow\left(x-6\right)\cdot\left(x+6\right)+\left(x-6\right)^2=0\)

\(\Leftrightarrow\left(x-6\right)\cdot\left[\left(x+6\right)+\left(x-6\right)\right]=0\)

\(\Leftrightarrow\left(x-6\right)\cdot2x=0\)

\(\Rightarrow\left[{}\begin{matrix}x-6=0\\2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=6\\x=0\end{matrix}\right.\)