>>479
Me too, I solve 2-degree equation like this:
 \begin{math} 
x^2+ax+b=0\\
x=p+iq \end{math} 
where  \begin{math}i^2=-1\end{math}
\begin{math}
\\(p+iq)^2+a(p+iq)+b=0\\
\begin{cases}
p^2-q^2+ap+b=0\\
2iqp+aiq=0
\end{cases}
\\ \begin{cases}
q=\pm \sqrt{\frac{a^2}{4}+a\frac{a}{2}+b}
\\p=-\frac{a}{2}
\end{cases}
 \end{math}
because i don't remember formula.