$$ \begin{aligned} \frac{3}{4}r-2 &= 2 \cdot \frac{r}{5}+1&& \text{multiply ALL terms by } \color{blue}{ 20 }. \\[1 em]20 \cdot \frac{3}{4}r-20\cdot2 &= 20\cdot2 \cdot \frac{r}{5}+20\cdot1&& \text{cancel out the denominators} \\[1 em]15r-40 &= 8r+20&& \text{move the $ \color{blue}{ 8r } $ to the left side and $ \color{blue}{ -40 }$ to the right} \\[1 em]15r-8r &= 20+40&& \text{simplify left and right hand side} \\[1 em]7r &= 60&& \text{ divide both sides by $ 7 $ } \\[1 em]r &= \frac{60}{7}&& \\[1 em] \end{aligned} $$

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