# If one zero of the polynomial 4x2 – 8kx – 9 is the negative of the other. Find the value of k?

The polynomial 4x2 – 8kx – 9 is quadratic hence it will have two zeroes

Let one zero of polynomial be α

As the other one is negative hence it would be –α

Thus, α and –α are roots of 4x2 – 8kx – 9

Compare 4x2 – 8kx – 9 with ax2 + bx + c = 0

a = 4, b = –8k and c = –9

Sum of roots of quadratic =

Substituting the value of b and a

8k = 0

k = 0

Hence k = 0

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