Find the value of K, for which the quadratic equation x² + 4x + K = 0 has equal roots.

Correct option is C

Given:

Quadratic equation: x² + 4x + K = 0

We are to find the value of K for which the equation has equal roots.

Formula Used:

Discriminant D = b² - 4ac

For equal roots: D = 0

Solution:

Here, a = 1, b = 4, c = K

Substitute in the discriminant formula:

4² - 4(1)(K) = 0

16 - 4K = 0

4K = 16

K = 4