$$ \begin{aligned} -2(9x-1) &= -(x-9)-7x&& \text{simplify left and right hand side} \\[1 em]-(18x-2) &= -x+9-7x&& \\[1 em]-18x+2 &= -8x+9&& \text{move the $ \color{blue}{ -8x } $ to the left side and $ \color{blue}{ 2 }$ to the right} \\[1 em]-18x+8x &= 9-2&& \text{simplify left and right hand side} \\[1 em]-10x &= 7&& \text{ divide both sides by $ -10 $ } \\[1 em]x &= -\frac{7}{10}&& \\[1 em] \end{aligned} $$

This page was created using