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Proof of quadratic formula

Proof of Quadratic Formula

Completing the square and the quadratic formula

Solving quadratic equations by square roots
Solving quadratic equations by completing the square
How to use the quadratic formula
Proof of quadratic formula
Example: Complex roots for a quadratic
Discriminant of quadratic equations
Discriminant for types of solutions for a quadratic

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This collection was created November 2014.