If x = –3 is the only x-intercept of the graph of a quadratic equation, which statement best describes the discriminant of the equation? The discriminant is negative. The discriminant is –3. The discriminant is 0. The discriminant is positive.
[tex]\text{ if } \Delta=0\text{ then there is one x-intercept : }x=-\dfrac{b}{2a}\\\\
\text{ if } \Delta\ \textless \ 0\text{ then there are no x-intercept : } x=\varnothing\\\\
\text{ if } \Delta>0\text{ then there are two x-intercept : }x_1,x_2=\dfrac{-b\pm\sqrt{\Delta}}{2a}\\\\[/tex]
