$$ \begin{aligned} 9-5\cdot(7+4x\cdot4) &= 4\cdot(7+4x\cdot4)&& \text{simplify left and right hand side} \\[1 em]9-5\cdot(7+16x) &= 4\cdot(7+16x)&& \\[1 em]9-(35+80x) &= 28+64x&& \\[1 em]9-35-80x &= 64x+28&& \\[1 em]-80x-26 &= 64x+28&& \text{move the $ \color{blue}{ 64x } $ to the left side and $ \color{blue}{ -26 }$ to the right} \\[1 em]-80x-64x &= 28+26&& \text{simplify left and right hand side} \\[1 em]-144x &= 54&& \text{ divide both sides by $ -144 $ } \\[1 em]x &= -\frac{54}{144}&& \\[1 em]x &= -\frac{3}{8}&& \\[1 em] \end{aligned} $$

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