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The discriminant is the number we end up with under the square root in the
_______________ ______________.
The discriminant of ax2 + bx + c = 0 is:
First, make sure the equation is set equal to ____ and identify a, b, and c.
Plug the values into the expression b2 – 4ac and simplify.
Find the discriminant of 3x2 + 4x – 8 = 0.
a = ____
b = ____
c = ____
Discriminant =
The discriminant tells us:
1) ________ ____________ solutions there are.
2) How many times the graph crosses the ___________.
3) If the solutions are real or ______________.
If the discriminant is positive, the quadratic equation
will have _____ _________ solutions.
The graph will have ____ x-intercepts.
Will the discriminant tell you exactly where the graph crosses the x-axis? _____
You can use the __________________ ________________ to find the specific answers.
If the discriminant is zero, the quadratic equation will
have ____ ___________ solution.
The graph will have ____ x-intercept. The parabola
will hit the x-axis at its maximum or ______________ point.
You can take the square root of a negative number, but the answer is _______ _________.
The square root of a negative number will involve the imaginary number ____. If the
solutions are complex, you will not see them on the _____________.
If the discriminant is negative, the quadratic equation will have
____ ______________ solutions. The graph will have ______ x-intercepts.
Find the discriminant
3x2 – 8x + 2 = 0
x2 + 7x – 8 = 0
4x2 - 12x + 9 = 0
. Discriminant = 8. The graph will have ____ x-intercept(s).
Discriminant = 0. The graph will have ____ x-intercept(s).
Discriminant = -4. The graph will have ____ x-intercept(s).
The discriminant of -2x2 + 5x – 6 = 0 is _____.
Which statement is true about the graph? ______________________________________
The discriminant of 9x2 – 6x + 1 = 0 is ______.
Sketch the correct graph:
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