Given 2x² = -8 IMPLIES
x^2 = -4 (which is -8/2),
and it means that x can not be real number.
This equation HAS NO solutions in real numbers.
It has solutions in complex number domain.
In complex number domain, equation
x^2 = -4
has two roots
x = = +/- 2i,
where " i " is complex imaginary units i = .
So, again, the original equation has no real roots;
it has two complex roots 2i and -2i.