Respuesta :

The answer would be B. Using the foil method to check, the two k's equal k^2, then the k and -f would equal -fk, plus the 2fk would equal a positive fk. Lastly, the 2f and -f would equal -2f^2.
[tex]k^2+kf-2f^2[/tex]
=[tex]k^2+kf-f^2-f^2[/tex]
=[tex]k^2-f^2+kf-f^2[/tex]
=[tex](k+f)(k-f)+f(k-f)[/tex]
=[tex](k+2f)(k-f)[/tex]
B