\(4x\left(x-5\right)-\left(x-5\right)^2=0\)
\(\left(x-5\right)\left(4x-x+5\right)=0\)
\(\left(x-5\right)\left(3x+5\right)=0\)
\(=>\left[{}\begin{matrix}x-5=0\\3x+5=0\end{matrix}\right.< =>\left[{}\begin{matrix}x=5\\x=-\dfrac{5}{3}\end{matrix}\right.\)
b)
\(3x^2-5x-2=0\)
\(3x^2-6x+x-2=0\)
\(3x\left(x-2\right)+\left(x-2\right)=0< =>\left(x-2\right)\left(3x+1\right)=0< =>\left[{}\begin{matrix}x-2=0\\3x+1=0\end{matrix}\right.< =>\left[{}\begin{matrix}x=2\\x=-\dfrac{1}{3}\end{matrix}\right.\)
<=> \(\left(x-5\right)\left(4x-x+5\right)=0\)
<=>\(\left(x-5\right)\left(3x-5\right)=0\)
=>\(\left\{{}\begin{matrix}x-5=0\\3x-5=0\end{matrix}\right.=>\left\{{}\begin{matrix}x=5\\x=\dfrac{3}{5}\end{matrix}\right.\)
