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