Question

find the value of k for which the quadratic equation X square + 4 x + K equal to zero has real and distinct roots

Answer 1

hence
${b }^{2} - 4ac > 0 \\ 16 > 4 \times 1 \times k \\ k < 4$

Answer 2

$x {}^{2} + 4x + k \\ 0 < b {}^{2} - 4ac \\ 0 < 4 {}^{2} - 4 \times 1 \times k \\ 0 < 4 {}^{2} - 4k \\ 0 <4(4 - k) \\ 0 < 4 - k \\ k < 4$