$\frac{2}{3}x + \frac{1}{4} = 8\frac{1}{4} = \frac{33}{4}$

$\frac{2}{3}x = \frac{33}{4} - \frac{1}{4} = \frac{32}{4} = 8$

$x = 8 \times \frac{3}{2} = 12$