ЯКЛАСС, Срочнно нужно решить задание

Решите задачу:

$1)\frac{r^{2}-5r+25} {25r^{2}-1}* \frac{5r^{2}+r} {r^{3}+125}= \frac{r^{2}-5r+25} {(5r-1)(5r+1)}* \frac{r(5r+1)}{(r+5)(r^{2}-5r+25)}= \frac{r}{(5r-1)(r+5)}\\\\2) \frac{r}{(5r-1)(r+5)} -\frac{r+5}{5r^{2}-r}= \frac{r}{(5r-1)(r+5)}- \frac{r+5}{r(5r-1)} = \frac{r^{2}-r^{2}-5r-5r-25}{r(5r-1)(r+5)}= \frac{-10r-25}{r(5r-1)(r+5)}= \frac{-5(2r+5)}{r(5r-1)(r+5)}$

$3)\frac{-5(2r+5)}{r(5r-1)(r+5)} :\frac{7}{r^{2}+5r}= \frac{-5(2r+5)}{r(5r-1)(r+5)}* \frac{r(r+5)}{7}=- \frac{5(2r+5)}{7(5r-1)}\\\\4) \frac{-5(2r+5)}{7(5r-1)}- \frac{25r+22}{7-35r}= \frac{25r+22}{7(5r-1)}- \frac{5(2r+5)}{7(5r-1)}= \frac{25r+22-10r-25}{7(5r-1)}= \frac{15r-3}{7(5r-1)}= \frac{3(5r-1)}{7(5r-1)}= \frac{3}{7}$