Question

For what value of k, (−4) is a zero of the polynomial x2 − x − (2k + 2)?

Answer 1

Hey Mate..
Let p(x) = x2 − x − (2k + 2).

If (−4) is a zero of p(x), then p (−4) = 0.

p(−4) = 0

Þ (−4)2 − (−4) − 2k − 2 = 0

Þ 16 + 4 − 2k − 2 = 0

Þ 18 − 2k = 0

Þ 2k = 18

Þ k = 9

Thus, the required value of k is 9.

Answer 2

let p(x)= x2 -x-(2k+2)
given zero is -4
so,
p(-4)=(-4)2-(-4)-(2k+2)=0
16+4-2k-2=0
20-2k-2=0
18-2k=0
-2k=-18
2k=18
k=18/2
k=9
value of k is 9