Question

1. Use the discriminant to determine allvalues of k which would result in theequation (In the photo) having imaginaryroots.

Answer 1

given data:

The given quadratic equation is

$2x^2+8x+k=0$

To find the value of the discriminant and determinte all the values of k that would result in having imaginary root.

The discriminant is a part of the quadratic formula that is under the square root,

$b^2-4ac$

now, from the given quadratic equation,

a= 2, b=8 and c=k.

subsitute the above values in the discriminant formula,

$\begin{gathered} (8)^2-4\cdot2\cdot k \\ 64-8k \end{gathered}$

for the roots to be imaginary the roots should be negative fo that value of k should be greater than 8.

$k>8$