# How do you solve the quadratic using the quadratic formula given a^2-5a+8=0?

Oct 18, 2016

$a = \frac{5 \pm i \sqrt{7}}{2}$
$\Delta = {b}^{2} - 4 a c = 25 - 32 = - 7$
$\Delta < 0$
$\sqrt{\Delta} = i \sqrt{7}$
so there are no solutions in $\mathbb{R}$ but in $\mathbb{C}$
$a = \frac{5 \pm i \sqrt{7}}{2}$