Đáp án:
$\frac{-4}{x}$ = $\frac{-6}{9}$
⇔ x = $\frac{-4.(-9)}{6}$ = 6
Vậy x = 6.
x+$\frac{1}{3}$ = x - $\frac{1}{2}$
⇔ 2x = -1/2 - 1/3
⇔ x /= -5/12
Vậy x = -5/12
c. x/2 = 6/x+1
⇔ x² + x= 12
⇔ x²+x-12 = 0
⇔ \(\left[ \begin{array}{l}x=3\\x=-4\end{array} \right.\)
Vậy x ∈ {3; -4}