b) x/6 - 1/2 = 2/3

* Hướng dẫn giải

$\begin{array}{l}b) \frac{\mathrm{x}}{6}-\frac{1}{2}=\frac{2}{3}\\ \frac{\mathrm{x}}{6}=\frac{2}{3}+\frac{1}{2}\\ \frac{\mathrm{x}}{6}=\frac{2.2}{3.2}+\frac{1.3}{2.3}\\ \frac{\mathrm{x}}{6}=\frac{4}{6}+\frac{3}{6}\\ \frac{\mathrm{x}}{6}=\frac{7}{6}\\ \mathrm{x}=7\\ \mathrm{Vậy} \mathrm{x}=7\end{array}$