Question

10b^2-10a^2/(10a-10b)^2

Answer 1

$\frac{10b^2-10a^2}{(10a-10b)^2}= \frac{-10(a^2-b^2)}{10^2(a-b)^2}= \frac{-10(a-b)(a+b)}{10^2(a-b)^2}=- \frac{a+b}{10(a-b)}=\frac{a+b}{10b-10a}$