a)
$\dfrac{2}{3} - \dfrac{1}{3}(x - \dfrac{3}{2}) - \dfrac{1}{2}(2x + 1) = 5$
$\dfrac{2}{3} - \dfrac{1}{3}x + \dfrac{1}{2} - x - \dfrac{1}{2} = 5$
$\dfrac{-4}{3}x = 5 - \dfrac{2}{3}$
$\dfrac{-4}{3}x = \dfrac{13}{3}$
$x = \dfrac{-13}{4}$
b) Tương tự câu a)
c) $\dfrac{2}{9} .x .(x - 3\tfrac{7}{8}) = 0$
Suy ra $x = 0$ hoặc $x - 3\tfrac{7}{8} = 0$
Hay $x = 0$ và $x = 3\tfrac{7}{8}$