Question

Помогите пожалуйста!!!!

Answer 1

$frac{1}{9}c^{2}-frac{16}{25}d^{2}=(frac{1}{3}c)^{2}-(frac{4}{5}d)^{2}=(frac{1}{3}c-frac{4}{5}d)(frac{1}{3}c+frac{4}{5}d)$