Answer
$x = \frac{5±\sqrt{7}i}{2}$
Work Step by Step
$x^2 - 5x + 8 = 0$
Use the quadratic formula: $x = \frac{-b±\sqrt{b^2-4ac}}{2a}$
$a=1$, $b=-5$, $c=8$
$x = \frac{-(-5)±\sqrt{(-5)^2-(4⋅1⋅8)}}{(2⋅1)}$
$x = \frac{5±\sqrt{25-32}}{2}$
$x = \frac{5±\sqrt{-7}}{2}$
$x = \frac{5±\sqrt{7}i}{2}$
