Answer
$$x=\frac{-4+\sqrt{21}}{2},\:x=-\frac{4+\sqrt{21}}{2}$$
Work Step by Step
The quadratic formula states:
$$x_{1,\:2}=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$$
Thus, solving the equation, we find:
$$ x_{1,\:2}=\frac{-16\pm \sqrt{16^2-4\cdot \:4\left(-5\right)}}{2\cdot \:4} \\ x=\frac{-4+\sqrt{21}}{2},\:x=-\frac{4+\sqrt{21}}{2}$$
