Question

For what value of “k” will the equation (2kx2 + 5kx +2)=0 have equal roots?

Answer 1

d=0
b^2 -4ac=0
25k2-4(2K)(2)=0
25k2=16k
k=4/5

Answer 2

2kx² + 5kx +2 = 0

The quadratic equation has equal roots

⇒ the discriminant = 0

Solve x:

Discriminant = b² - 4ac

Given that a = 2k, b = 5k, c = 2

b² - 4ac = 0

(5k)² - 4(2k)(2) = 0

25k² - 16k = 0

k(25k - 16) = 0

k = 0 or 25k - 16 = 0

k = 0 or k = 16/25

Answer: k = 0 or k = 16/25