$\dfrac{4}{9}\times (\dfrac{7}{2}-1\dfrac{1}{4})-\frac{3}{4}\times x = \dfrac{1}{2}$
$\dfrac{4}{9}\times (\dfrac{7}{2}-\dfrac{5}{4}) -\dfrac{3}{4}\times x=\dfrac{1}{2}$
$\dfrac{4}{9}\times (\dfrac{14}{4}-\dfrac{5}{4})-\dfrac{3}{4}\times x =\dfrac{1}{2}$
$\dfrac{4}{9}\times \dfrac{9}{4}-\dfrac{3}{4}\times x =\dfrac{1}{2}$
$1-\dfrac{3}{4}\times x =\dfrac{1}{2}$
$\dfrac{3}{4}\times x = 1-\dfrac{1}{2}$
$\dfrac{3}{4}\times x=\dfrac{1}{2}$
$x=\dfrac{1}{2}:\dfrac{3}{4}$
$x=\dfrac{2}{3}$
