Question

for what value of k, the roots of quadratic equation kx (x-2✓5)+10=0. are equal

Answer 1

Kx(x - 2√5) + 10 = 0
Kx² - 2√5Kx + 10 = 0

A/C to question,
roots of this quadratic equation are equal.
hence, discriminant = D = b² - 4ac = 0
so , (-2√5k)² - 4 × 10 × K = 0
20K² - 40K = 0
20K( K - 2) = 0 => K = 0, 2
but K ≠ 0 because if K = 0 , then equation can't be quadratic equation.

hence, K = 2

Answer 2

here D=bsquare-4ac
d=0 given in question