Question

Find the range of values of k for which the equation kx2+7x-4=0 has imaginary roots

Answer 1

Step-by-step explanation:

$k {x}^{2} + 7x + 4 = 0 \\ \\ {d}^{} = {7}^{2} - 4(k)(-4) = 49 - 16k \\ \\ d < 0 \\ \\ 49 +16k < 0 \\ \\ 49 < -16k \\ \\ k <- \frac{49}{16} . \\ \\ therefore \: \: k \: belongs \: to \: \: ( - infinity \: \: \: \: \: \frac{-49}{16}).$