Discriminant

Front

What does the discriminant tell us?

Back

The number and type of solutions of a quadratic equation.

Tags

CCSS.HSA-REI.B.4B

Front

What is the discriminant of the equation -2x² - x - 1 = 0?

Back

-7

Tags

CCSS.HSA-REI.B.4B

Front

If the discriminant is positive, what can we say about the solutions of the quadratic equation?

Back

There are two distinct real solutions.

Tags

CCSS.HSA-REI.B.4B

Front

If the discriminant is zero, what can we say about the solutions of the quadratic equation?

Back

There is exactly one real solution (a repeated root).

Tags

CCSS.HSA-REI.B.4B

Front

If the discriminant is negative, what can we say about the solutions of the quadratic equation?

Back

There are no real solutions (the solutions are complex).

Tags

CCSS.HSA-REI.B.4B

Front

A function has a discriminant of 4. How many x-intercepts does it have?

Back

2

Tags

CCSS.HSA-REI.B.4B

Front

What is the formula for the discriminant of a quadratic equation ax² + bx + c = 0?

Back

D = b² - 4ac.

Tags

CCSS.HSA-REI.B.4B

Front

What does a positive discriminant indicate about the graph of a quadratic function?

Back

The graph intersects the x-axis at two points.

Tags

CCSS.HSA-REI.B.4B

Front

What does a zero discriminant indicate about the graph of a quadratic function?

Back

The graph touches the x-axis at one point (vertex).

Tags

CCSS.HSF-IF.C.7A

Front

What does a negative discriminant indicate about the graph of a quadratic function?

Back

The graph does not intersect the x-axis.

Tags

CCSS.HSA-REI.B.4B