$-80-12y \leq -30$
Move the constant to the right-hand side and change its sign$-12y \leq -30+80$
Calculate the sum$-12y \leq 50$
Divide both sides of the inequality by $-12$ and flip the inequality sign$\begin{align*}&y \geq -\frac{ 25 }{ 6 } \\&\begin{array} { l }\begin{array} { l }\begin{array} { l }y \geq -4 \frac{ 1 }{ 6 },& y \geq -4.1\overset{ \cdot }{ 6 } \end{array},& y \in \left[ -\frac{ 25 }{ 6 }, +\infty\right\rangle\end{array}\end{array}\end{align*}$