Сократите дробь: (x^2-10x+25)/(25-x^2).

\[\frac{x^{2} - 10x + 25}{25 - x^{2}} =\]

\[= \frac{(5 - x)^{2}}{(5 - x)(5 + x)} = \frac{5 - x}{5 + x}.\]