7. Use the discriminant to determine how many real number solutions exist for the quadratic equation –4j2 + 3j – 28 = 0.

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

so.. check what value the discriminant is then.