8/3 - 5/3 x = 7/10 x + 5/6
7/10 x + 5/3 x = 8/3 - 5/6
71/30 x = 11/6
x = 11/6 : 71/30
x = 55/71
\(\Leftrightarrow\dfrac{8}{3}-\dfrac{5x}{3}=\dfrac{7x}{10}+\dfrac{5}{6}\\\Leftrightarrow\dfrac{8}{3}-\dfrac{5x}{3}-\dfrac{7x}{10}-\dfrac{5}{6}=0\\ \Leftrightarrow\dfrac{80}{30}-\dfrac{50x}{30}-\dfrac{21x}{30}-\dfrac{25}{30}=0\\ \Leftrightarrow80-50x-21x-25=0\\ \Leftrightarrow55-71x=0\\ \Leftrightarrow71x=55\\ \Leftrightarrow x=\dfrac{55}{71} \)