Respuesta :

First distribute 
=(k)(k)+(k)(−9)+(−4)(k)+(−4)(−9)=k2+−9k+−4k+36

Combine Like Terms:=k2+−9k+−4k+36=(k2)+(−9k+−4k)+(36)=k2+−13k+36

The answer is k^2-13k+36