$\left( 2x - \dfrac{3}{4} \right) - \left( x - \dfrac{5}{6} \right) = (x + 2) - (x - 1)$

$2x - \dfrac{3}{4} - x + \dfrac{5}{6} = x + 2 - x + 1$

$(2x - x) - \dfrac{9}{12} + \dfrac{10}{12} = (x - x) + 2 + 1$

$x + \dfrac{1}{12} = 3$

$x = 3 - \dfrac{1}{12}$

$x = \dfrac{36}{12} - \dfrac{1}{12}$

$x = \dfrac{35}{12}$

Vậy $x = \dfrac{35}{12}$