5x(1-2x) - 3x( x+18) = 0
⇔ ( 5x - 10x² ) - ( 3x²+54x) = 0
⇔ 5x - 10x² -3x² - 54x =0
⇔ -49x -13x² =0
⇔ x ( -49-13x) = 0
⇔ \(\left[ \begin{array}{l}x=0\\-49-13x=0\end{array} \right.\) ⇔\(\left[ \begin{array}{l}x=0\\x=-\frac{49}{13} \end{array} \right.\)
Vậy x = 0 hoặc x = -$\frac{49}{13}$
cho mình xin tlhn nhé