The expressions (x+4) is a factor of x2+kx-20 what is the value of k how do you know

k = - 1

Step-by-step explanation:

You're given (x+4) as one of the factor for the equation

x² + kx - 20 = 0

what number does 4 multiply with to get - 20? It's - 5.

So

= (x+4) (x-5)

= x² + - 1x - 20

= x² + kx - 20