9-6 Quadratic Formula

9-6 Quadratic Formula

Author: Kate Sidlo

By the end of this tutorial students will be able to plug in values to the discriminant to find the number of roots, and plug in values to the quadratic formula to find the value of the root or roots.

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1) Write title at the top of the page

2) Draw Cornell Line

3) Write all questions & answers

4) Write all examples

9-6 Quadratic Formula & Discriminant


DISCRIMINANT: The part of the quadratic formula under the square root (b2 - 4ac).  Tells the number of roots.

FACTORED FORM: Any quadratic equation in the form y = (x - a)(x - b)

FACTORING: To break up terms into smaller like terms (for this unit, to go from standard to factored form)

LINE OF SYMMETRY: The vertical line through the vertex, splits parabola into two mirror-image pieces

QUADRATIC EQUATION: A polynomial with a highest term of x2

QUADRATIC FORMULA: Formula solves for the roots of any standard form quadratic equation

PARABOLA: A graph of a quadratic equation

POLYNOMIAL: Any finite set of terms with positive exponents being added, subtracted, or multiplied

ROOTS/ZEROS: The point or points where a parabola intersects the x-axis.

STANDARD FORM: Any quadratic equation in the form: y = ax2 + bx + c

VERTEX: The point on the graph where the parabola changes direction from positive to negative or negative to positive