\[x = - 1,5\]
\[\frac{5 - 3x}{25 - x^{2}} + \frac{2x}{25 - x^{2}} =\]
\[= \frac{5 - 3x + 2x}{25 - x^{2}} =\]
\[\frac{1}{5 + ( - 1,5)} = \frac{1}{5 - 1,5} =\]
\[= \frac{1}{3,5} = \frac{1}{\frac{7}{2}} = \frac{2}{7}\]