Question

9x^2-6x=8

Answer 1

\(9x^2-6x=8\)

\(9x^2-6x+1=9\)

\(\left(3x-1\right)^2=\left(\pm3\right)^2\)

\(\left[\begin{array}{nghiempt}3x-1=3\\3x-1=-3\end{array}\right.\)

\(\left[\begin{array}{nghiempt}3x=3+1\\3x=-3+1\end{array}\right.\)

\(\left[\begin{array}{nghiempt}3x=4\\3x=-2\end{array}\right.\)

\(\left[\begin{array}{nghiempt}x=\frac{4}{3}\\x=-\frac{2}{3}\end{array}\right.\)

Answer 2

9x²-6x=8

<=>9x²-6x+1=9

<=>(3x-1)²=9

<=> 3x-1 = \(\pm3\)

<=> 3x-1=-3 hoặc 3x-1=3

=> \(x=\frac{-2}{3}\) hoặc \(x=\frac{4}{3}\)