a)
\(\left(3x-1\right)^2-25=0\\ \left(3x-1-5\right)\left(3x-1+5\right)=0\\ \left(3x-6\right)\left(3x+4\right)=0\\ \left[{}\begin{matrix}3x-6=0\\3x+4=0\end{matrix}\right.\left[{}\begin{matrix}x=2\\x=-\dfrac{4}{3}\end{matrix}\right.\)
b)
xem lại đề sai ko nhé