Answer
$$u=\frac{3+\sqrt{5}}{5},\:u=\frac{3-\sqrt{5}}{5}$$
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:
$$ u_{1,\:2}=\frac{-\left(-30\right)\pm \sqrt{\left(-30\right)^2-4\cdot \:25\cdot \:4}}{2\cdot \:25} \\ u=\frac{3+\sqrt{5}}{5},\:u=\frac{3-\sqrt{5}}{5}$$
