\(\bf 9x^2+12x+4=0\\\
\begin{array}{lcclll}
9x^2&+12x&+4&=y\\
\uparrow &\uparrow &\uparrow \\
a&b&c
\end{array}\qquad
\begin{cases}
discriminant\to b^2-4ac\\\\
\textit{if negative}\\
\textit{no solutions}\\
----------\\
\textit{if positive}\\
\textit{two real solutions}\\
----------\\
\textit{if 0}\\
\textit{one solution}
\end{cases}\)
