Question

for what value of k,-2 is a zero of the polynomial 3x² + 4x + 2k.

Answer 1

Answer:

k = -2

Step-by-step explanation:

I have attached an image now you can clear your doubts

Answer 2

Given

• Polynomial = 3x² + 4x + 2k
• One zero of the polynomial is -2.

To find

• Value of k.

Solution

$\sf\pink{⟶}$ Firstly we put x = -2 (as it is zero of the polynomial).

$\tt:\implies\: \: \: \: \: \: \: \: {p(x) = 3x^2 + 4x + 2k}$

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$\tt:\implies\: \: \: \: \: \: \: \: {p(-2) = 3(-2)^2 + 4(-2) + 2k}$

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$\tt:\implies\: \: \: \: \: \: \: \: {p(-2) = 3 \times{4} + (-8) + 2k}$

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$\tt:\implies\: \: \: \: \: \: \: \: {p(-2) = 12 - 8 + 2k}$

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$\tt:\implies\: \: \: \: \: \: \: \: {4 + 2k}$

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$\sf\pink{⟶}$ Put p(x) [4 + 2k] = 0.

⠀

$\tt:\implies{4 + 2k = 0}$

$\tt:\implies{2k = -4}$

$\tt:\implies{k = \dfrac{-4}{2}}$

$\tt:\implies{k = -2}$

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