$$ \begin{split} 3\cdot(x +4)&= -2\cdot(x +8)\\ \rightarrow 3\cdot x +12 = -2x -16\\ \rightarrow 3\cdot x +2x +12 -12 = -2x +2x -16 -12\\ \rightarrow 5\cdot x = -28\\ \\ \rightarrow x = \frac{-28}{5}= -\frac{28}{5} \end{split} $$