$$ \begin{aligned} r-3\cdot(1-2(3r+5)) &= 46&& \text{simplify left side} \\[1 em]r-3\cdot(1-(6r+10)) &= 46&& \\[1 em]r-3(1-6r-10) &= 46&& \\[1 em]r-3(-6r-9) &= 46&& \\[1 em]r-(-18r-27) &= 46&& \\[1 em]r+18r+27 &= 46&& \\[1 em]19r+27 &= 46&& \text{ move 27 to the right } \\[1 em]19r &= 46-27&& \\[1 em]19r &= 19&& \text{ divide both sides by $ 19 $ } \\[1 em]r &= \frac{19}{19}&& \\[1 em]r &= 1&& \\[1 em] \end{aligned} $$

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