Question

find the value of k if (x+k) is a factor of the polynomial x³+kx²-2x+k+y

Answer 1

X+k=0
Then,
x=-k
P(x)=x^3+kx^2-2x+k+y=0
P(-k)=(-k)^3+k(-k)^2-2(-k)+k+y=0
=-k^3+k^3+2k+k+y=0
=2k+k+y=0
=3k+y=0
=k= -y/3

Answer 2

here your answer:-

x+k=0
x=-k