Question

Which of the following is a solution of x2 + 4x = −8?

Answer 1

$x^{2}+4x = -8 \\\\ x^{2}+4x+8 = 0 \\\\ \Delta = b^{2}-4ac \\\\ \Delta = (4)^{2}-4 \cdot (1) \cdot (8) \\\\ \Delta = 16-32 \\\\ \Delta = -16$

There's no solution in the set of real numbers.

$\boxed{S = \{ \ \ \}}$