Question

find the value of k if x-1 is a factor of p(x) in each of the following
p(x)=square of x+x+k

Answer 1

I think k must be -2

Answer 2

$x^{2} +x+k=(x-1)(x+a) \\ x^{2} +x+k= x^{2} +(a-1)x-a \\ a-1=1,a=2 \\ k=-a=-2$