The discriminant of a quadratic equation is given by:
[tex]\begin{gathered} b^2-4ac \\ \text{with the quadratic equation in the form} \\ ax^2+bx+c=0 \end{gathered}[/tex]•When the calculation of the discriminant gives a negative number, the equation has two complex roots
•when the discriminant is zero, the equation has a root, double root
•when the calculation of the discriminant is a positive number, the equation has two distinct roots.
the given quadratic equation is
[tex]\begin{gathered} x^2+4x+7=0 \\ \text{In this equation, the coefficients will tell us that values for }a,b,\text{ and }c \\ a=1 \\ b=4 \\ c=7 \end{gathered}[/tex]Substitute these values to get the discriminant.
[tex]\begin{gathered} b^2-4ac \\ =(4)^2-4(1)(7) \\ =16-28 \\ =-12 \end{gathered}[/tex]Since the discriminant is negative, we can conclude that there is two complex solutions.