Question

Can anyone solve this plzz...
find the value of k given that (x+3 ) is a factor of x^3 +4x +kv-24



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Answer 1

AnswEr:

the value of k is -21.

ExplanaTion:

Given that, (x+3) is a factor of Polynomial p(x) = x³ + 4x + kx - 24

Put x + 3 = 0

$\implies$ x = -3

Substitute x = -3 in polynomial p(x).

$\implies$ (-3)³ + 4(-3) + k(-3) - 24

$\implies$ -27 - 12 - 3k - 24

$\implies$ -3k - 63

Equate it to zero.

$\implies$ -3k - 63 = 0

$\implies$ -3k = 63

$\implies$ k = $\dfrac{63}{-3}$

$\implies$ k = -21

Hence, the value of k is -21.

Answer 2

Correct Question: Find the value of k given that (x + 3) is a factor of x³ + 4x + kx - 24

GIVEN:

Polynomial = x³ + 4x + kx - 24

Factor of polynomial = x + 3

TO FIND:

Value of k

SOLUTION:

If x + 3 is the factor of p(x) = x³ + 4x + kx - 24 then the value of p(-3) = 0

=> p(-3) = x³ + 4x + kx - 24

=> (-3)³ + 4(-3) + k(-3) - 24 = 0

=> -27 - 12 - 3k - 24 = 0

=> -63 - 3k = 0

=> -3k = 63

=> k = 63/-3

=> k = -21

Therefore, the value of k is -21.