Question

Помогите решить №315

Answer 1

$\frac{7a}{(a-5b)(a+5b)}*b(a+5b)= \frac{7ab}{a-5b}$

Answer 2

$\frac{7a}{a^{2}-25b^{2}}*(ab+5b^{2})=\frac{7a*b(a+5b)}{(a+5b)(a-5b)}=\frac{7ab}{a-5b}$