11) \(\frac{a-7}{a^2}-\frac{15+2a}{a^2}=\)

\(\frac{a-7}{a^2}-\frac{15+2a}{a^2}=\frac{a-7-(15+2a)}{a^2}=\frac{a-7-15-2a}{a^2}=\frac{-a-22}{a^2}\).

Ответ: \(\frac{-a-22}{a^2}\)