\(4x^2-x^2+4x-4=0\\ 3x^2+4x-4=0\\ 3x^2+6x-2x-4=0\\ 3x\left(x+2\right)-2\left(x+2\right)=0\\ \left(3x-2\right)\left(x+2\right)=0\\ =>\left[{}\begin{matrix}3x-2=0\\x+2=0\end{matrix}\right.=>\left[{}\begin{matrix}x=\dfrac{2}{3}\\x=-2\end{matrix}\right.\)
4x2-(x-2)2=0
<=> (2x)2 - (x-2)2 = 0
<=> (2x -x+2)(2x+x-2) = 0
<=> \(\left[{}\begin{matrix}x+2=0\\3x-2=0\end{matrix}\right.=>\left[{}\begin{matrix}x=-2\\x=\dfrac{2}{3}\end{matrix}\right.\)
\(4x^2-\left(x-2\right)^2=0\)
\(\Leftrightarrow\left(2x+x-2\right)\left(2x-x+2\right)=0\)
\(\Leftrightarrow\left(3x-2\right)\left(x+2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}3x-2=0\\x+2=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{3}\\x=-2\end{matrix}\right.\)
