$$ \begin{aligned} \frac{2}{3}x+x-4+x &= 180&& \text{multiply ALL terms by } \color{blue}{ 3 }. \\[1 em]3 \cdot \frac{2}{3}x+3(x-4)+3x &= 3\cdot180&& \text{cancel out the denominators} \\[1 em]2x+3x-12+3x &= 540&& \text{simplify left side} \\[1 em]5x-12+3x &= 540&& \\[1 em]8x-12 &= 540&& \text{ move -12 to the right } \\[1 em]8x &= 540+12&& \\[1 em]8x &= 552&& \text{ divide both sides by $ 8 $ } \\[1 em]x &= \frac{552}{8}&& \\[1 em]x &= 69&& \\[1 em] \end{aligned} $$

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