Question

помогите, пожалусйта

Answer 1

$-n\left ( m^2+8n^2 \right )-7m\left ( -56n^2-7m^2 \right )=-n\left ( m^2+8n^2 \right )+49m\left ( m^2+8n^2 \right )=\left ( m^2+8n^2 \right )\left ( 49m-n \right )$