\[2\frac{1}{3} \cdot (a + 6) - 7\frac{2}{3} \cdot (3 - a) =\]
\[= \frac{7}{3}a + \frac{7}{3} \cdot 6 - \frac{23}{3} \cdot 3 + \frac{23}{3}a =\]
\[= \frac{7}{3}a + 14 - 23 + \frac{23}{3}a =\]
\[= \frac{30}{3}a - 9 = 10a - 9;\]
\[a = - 0,7:\]
\[10a - 9 = 10 \cdot ( - 0,7) - 9 =\]
\[= - 7 - 9 = - 16.\]