Đáp án:
$\text{x = 0 hoặc x = 12.}$
Giải thích các bước giải:
$\text{$\dfrac{1}{4}$.x² - 3x = 0.}$
$\text{⇒ x.($\dfrac{1}{4}$x - 3) = 0.}$
$\text{⇒ \(\left[ \begin{array}{l}x=0.\\\dfrac{1}{4}x-3=0.\end{array} \right.\)}$
$\text{⇒ \(\left[ \begin{array}{l}x=0.\\\dfrac{1}{4}x=3.\end{array} \right.\)}$
$\text{⇒ \(\left[ \begin{array}{l}x=0.\\x=3÷\dfrac{1}{4}.\end{array} \right.\)}$
$\text{⇒ \(\left[ \begin{array}{l}x=0.\\x=3.\dfrac{4}{1}.\end{array} \right.\)}$
$\text{⇒ \(\left[ \begin{array}{l}x=0.\\x=12.\end{array} \right.\)}$
$\text{Vậy x = 0 hoặc x = 12.}$
