Question

Find the value of k for which -4 is a zero of polynomial x2
-x –(2k+2)

Answer 1

Given :-

• -4 is a zero of the polynomial x² - x - (2k+2)

Solution :-

By the given information ,

⇒ x² - x - (2k+2) = 0 where x = - 4

⇒ (-4)² - 4 - (2k+2) = 0

⇒ 16 - 4 - (2k+2) = 0

⇒ 12 - (2k+2) = 0

⇒ 2k + 2 = 12

⇒ 2(k+1) = 12

⇒ k+1 = 6

⇒ k = 5

Conclusion :-

☯ K = 5

Answer 2

Question -:

Find the value of k for which -4 is a zero of polynomial

${x}^{2} - x - (2k + 2)$

lets try to solve the question

we have -4 as a zero

so x = -4 ( given )

Now put the value of x in above polynomial

$\dashrightarrow {x}^{2} - x - (2k + 2)$

$\dashrightarrow { - 4}^{2} - 4 - (2k + 2) = 0$

$\dashrightarrow \: 16 - 4 - (2k + 2) = 0$

$\dashrightarrow \: 12 - (2k + 2) = 0$

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

$\dashrightarrow \: 10 - 2k = 0$

$\dashrightarrow \: - 2k = - 10$

$\dashrightarrow \: k = \frac{10} - \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: {2}$

$\dashrightarrow \: k = 5$

Hence the value of k = 5

Hope this will help you

Thank you ..