Question

If 21 square = 400+40+k, then find k​

Answer 1

Answer:

In the given polynomial f(x)=x

2

−x−(2k+2), substitute x=−4 as shown below:

f(−4)=(−4)

2

−(−4)−(2k+2)=16+4−2k−2=18−2k

Therefore, f(−4)=18−2k.

Since it is given that x=−4 is a zero of the polynomial f(x)=x

2

−x−(2k+2), therefore f(−4)=0 that is:

18−2k=0

⇒2k=18

⇒k=

2

18

⇒k=9

Hence k=9.

Answer 2

Step-by-step explanation:

if 21 squre=400+40+k, then find k