Question

if x= -1 is a zero of the polynomial X2 +8x + k , then find the value of k

Answer 1

If x=-1

Then substitute the value of x in the polynomial p(x)=X2 +8x + k=0

When substituting

(-1)^2 + 8*(-1) +k =0

1-8+k=0

-7+k=0

K=7

Thus, k=7