2.102 упростить выражение

Решите задачу:

$\frac{121n^2-10pk-22pn+55kn}{66kn-11pn} * \frac{p^2-6pk}{121n^2-25k^2}=$

$=\frac{((121n^2+55kn)-(10pk+22pn))(p^2-6pk)}{(66kn-11pn)(121n^2-25k^2)}=$

$=\frac{(11n(11n+5k)-2p(11n+5k))*p(p-6k)}{11n(6k-p)(11n-5k)(11n+5k)}=$

$=\frac{(11n+5k)(11n-2p)*p(p-6k)}{11n(6k-p)(11n-5k)(11n+5k)}=$

$=\frac{-(11n-2p)*p(6k-p)}{11n(6k-p)(11n-5k)}=$

$=\frac{(2p-11n)*p}{11n(11n-5k)}=$

$=\frac{2p^2-11pn}{121n^2-55nk}$