Question

-If & and ß are the zeroes of
quadratic polynomial 2x²+kx-7
such that sum of the zeroes is.
twice their product, then the value
of K+2 is..​

Answer 1

Step-by-step explanation:

sum of zeroes = -k/2

product of zeroes = -7/2

it is given that sum = 2×product

-k/2 = 2×-7/2

-k = -14

k = 14

so the value of k + 2 = 14+2 =16

Answer 2

α and β are zeroes of quadratic polynomial 2x²+kx-7

then,

sum of zeroes, α+β = -b/a = -k/2

and

product of zeroes, αβ = c/a = -7 /2

it is given that sum of zeroes is twice their product

so,

α + β = 2 (αβ)

-k/2 = 2(-7/2)

-k/2 = -7

k/2 = 7

k = 7*2

k= 14

so,

k+2 = 14 + 2 = 16

HENCE, THE VALUE OF K+2 is 16.