[tex]\bf \begin{array}{lcccll}
& -4j^2& +3j& -28\\
&\uparrow &\uparrow &\uparrow \\
&a&b&c
\end{array}\qquad \qquad discriminant\implies b^2-4ac
\\\\\\
(3)^2-4(-4)(-28)=
\begin{cases}
0&\textit{one solution}\\
positive&\textit{two solutions}\\
negative&\textit{no solution}
\end{cases}[/tex]