__If sum of the square of zeros of the quadratic polynomial f(x)=x ^{2}-8x+k is 40 find the value of K__

Reply it fast..

given x^{2} + y^{2} = 40 (x and y are zeroes of quadratic equation)

we can write (x + y)^{2} - 2xy = 40 ------------------ 1

nw some of zeroes = x + y = -B/A = -(-8)=8

product of zeroes = xy = C/A = k

put value in equation 1

(8)^{2} - 2k = 40

64 - 40 = 2k

2k = 24

k = 12 answer

i think it will work

chill

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