$$ \begin{aligned} 2x+7-4(x+1) &= 5x+9&& \text{simplify left side} \\[1 em]2x+7-(4x+4) &= 5x+9&& \\[1 em]2x+7-4x-4 &= 5x+9&& \\[1 em]-2x+3 &= 5x+9&& \text{move the $ \color{blue}{ 5x } $ to the left side and $ \color{blue}{ 3 }$ to the right} \\[1 em]-2x-5x &= 9-3&& \text{simplify left and right hand side} \\[1 em]-7x &= 6&& \text{ divide both sides by $ -7 $ } \\[1 em]x &= -\frac{6}{7}&& \\[1 em] \end{aligned} $$

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