Question

if the product of zeroes of the quadratic polynomial 3x^2+5x+k is -2/3, find the value of k

Answer 1

X= -2/3

q(x) = 3x^2+5x+k

Put x= -2/3 in q(x)

q(-2/3) = 3(-2/3)^2+5(-2/3)+k = 0
= 3(4/9) + (-10/15) + k = 0
= 4/3 - 10/15 + k = 0
= (20 - 10 + 15k)/15 = 0
= 20 - 10 + 15k = 0*15
= 10 + 15k = 0
= 15 k = -10
= k = -10/15
= k = -2/3

Answer 2

Answer:

K= -2

Given

P(x)= 3x2+5x+k , product of zeroes = -2/3 ⇒ αβ= -2/3

αβ = c/a

⇒ -2/3=c/a

according to the question,

c/a= k/3

CROSS MULTIPLY

= -2/3=k/3

k =  -2

thnx