Question

Ifx=-3 is the only x-intercept of the graph of a quadratic equation, which statement best describes the discriminant of the

equation?

Answer 1

D = 0

Explanation:

Given

x-intercept = -3

Required

What does the discriminant represent?

The discriminant of a quadratic function can take any 3 values; these are as follows;

1. When D > 0
2. When D < 0
3. When D = 0

Which translates to

1. signifies that two different real roots exist
2. signifies that only complex roots exist
3. signifies that the two identical real roots exist

The question says that x-intercept = -3 is the only value;

This means that: x = -3 or x = -3

Analyzing the roots

1. 3 and -3 are identical
2. -3 and -3 are real

This means they satisfy condition number 3;

Hence, D = 0