\[9 \cdot (x + 2) - 7 \cdot (x - 2) = 0\]
\[9x + 18 - 7x + 14 = 0\]
\[2x + 32 = 0\]
\[2x = - 32\]
\[x = - 16\]
\[Ответ:\ x = - 16.\]