Respuesta :

you have to find out what x is because x is an imaginary number
Heya! I am going to show you something step by step, I hope this helps you hun.

=(x+−4)(x+5)

=(x)(x)+(x)(5)+(−4)(x)+(−4)(5)


=x2+5x4x−20


=x2+x20

(The 2 is to the second power between.) 

Please message me for further help! - Hannah