$$ \begin{aligned} -5y+13(y+11) &= -15(y-8)+7&& \text{simplify left and right hand side} \\[1 em]-5y+13y+143 &= -(15y-120)+7&& \\[1 em]8y+143 &= -15y+120+7&& \\[1 em]8y+143 &= -15y+127&& \text{move the $ \color{blue}{ -15y } $ to the left side and $ \color{blue}{ 143 }$ to the right} \\[1 em]8y+15y &= 127-143&& \text{simplify left and right hand side} \\[1 em]23y &= -16&& \text{ divide both sides by $ 23 $ } \\[1 em]y &= -\frac{16}{23}&& \\[1 em] \end{aligned} $$

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