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$ \frac{1 + x}{2017} + \frac{2 + x}{2016} + \frac{3 + x}{2015} = -3 \\ \Leftrightarrow \frac{1 + x}{2017} + 1 + \frac{2 + x}{2016} + 1 + \frac{3 + x}{2015} + 1 = 0 \\ \Leftrightarrow \frac{2018 + x}{2017} + \frac{2018 + x}{2016} + \frac{2018 + x}{2015} = 0 \\ \Leftrightarrow (2018 + x)\left ( \frac{1}{2017} + \frac{1}{2016} + \frac{1}{2015} \right ) = 0 \\ \frac{1}{2017} + \frac{1}{2016} + \frac{1}{2015} > 0 \\\Rightarrow 2018 + x = 0 \\\Leftrightarrow x = -2018 $
$ \frac{x + \frac{3x - 4}{5}}{15} = \frac{5 - \frac{3 - x}{2}}{5} - x + 1 \\ \Leftrightarrow \frac{\frac{8x - 4}{5}}{15} = \frac{\frac{10 - (3 - x)}{2} - 5x + 5}{5} \\ \Leftrightarrow \frac{8x - 4}{75} = \frac{\frac{10 - 3 + x - 10x + 10}{2}}{5} \\ \Leftrightarrow \frac{8x - 4}{75} = \frac{17 - 9x}{10} \\ \Leftrightarrow 75(17 - 9x) = 10(8x - 4) \\ \Leftrightarrow 1275 - 675x = 80x - 40 \\ \Leftrightarrow -755 x = -1315 \\ \Leftrightarrow x = \frac{263}{151} $