Question

if 2 is a zero of the polynomial ×^2-k×+8, then k=?​

Answer 1

Answer:

x² - kx + 8

one zero is 2

put 2 at place of x in the equation

2² - 2k + 8 = 0

4 - 2k + 8 = 0

12 - 2k = 0

-2k = -12

2k = 12

k = 6

Step-by-step explanation:

Hope this helps you :)

Answer 2

Answer:

k = 6

Step-by-step explanation:

$f( {x}) = {x}^{2} - kx + 8$

$\implies \: f(2) = {2}^{2} - 2k + 8$

$\implies \; f(2) = 4 - 2k + 8$

$\implies \: f(2) = 12 - 2k$

As 2 is a zero of f(x) so f(2) = 0

$f(2) = 0$

$\implies \: 12 - 2k \: = 0$

$\implies2k \: = 12$

$\implies \: k \: = 6$

∴ k = 6