Question

If the sum of zeroes of the quadratic polynomial 3x2 – kx + 6 is 3, then find the value of k.

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Answer 1

Answer:

The answer is $k=9$

Step-by-step explanation:

Concept : Sum of zeroes of the quadratic polynomial $ax^2+bx+c$ is $-\frac{b}{a}$

Thus sum of zeroes of $3x^2-kx+6$ is $=-(\frac{-k}{3})$

                    $\Rightarrow 3=\frac{k}{3}\\\Rightarrow k=3\times 3=9$

Answer 2

Answer:

9

Step-by-step explanation:

$\alpha + \beta$ = $\frac{-b}{a}$ = 3 ---> (Given)

So, by substituting the values of b and a in -b/a. We get

-(-k)/3 = 3

k/3 = 3

k =9