Question

please help asap 50 pts

Answer 1

$k^2+5kf-50f^2=k^2+10kf-5kf-50f^2\\\\=k(k+10f)-5f(k+10f)=(k+10f)(k-5f)\\\\\boxed{Answer:\ A.\ (k+10f)(k-5f)}$

Answer 2

id go with b honestly