Complete question:
If x = –3 is the only x-intercept of the graph of a quadratic equation, which statement best describes the discriminant of the equation?
a) The discriminant is negative.
b) The discriminant is –3.
c) The discriminant is 0.
d) The discriminant is positive.
Answer:
c) The discriminant is 0.
Explanation:
Here, x = -3 is the only x intercept of graph of a quadrant equation.
In this case the determinant of the quadrant equation will be 0.
i.e, x = 0
The determinant of the quadrant equation will be zero because, since x = -3 is the only x intercept of the graph, the quadrant equation will have equal roots. Also, when there are equal roots in a quadrant equation, the discriminant tends to zero.
Therefore the correct answer is (c) The discriminant is 0.
D = 0