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- Solving Quadratic Equations
Using quadratic formula to solve quadratic equations
- Intro Lesson7:19
- Lesson: 17:16
- Lesson: 23:56
- Lesson: 36:00
Using quadratic formula to solve quadratic equations
Not sure if you should solve the quadratic equation by factoring or completing the square? No worries. You can always use the quadratic formula. The beauty of the quadratic formula is that it can always give you the answer no matter if the quadratic equations can be factored or not.
Basic Concepts: Quadratic function in general form: y=ax2+bx+c, Shortcut: Vertex formula, Multiplying and dividing radicals
Related Concepts: System of quadratic-quadratic equations, Graphing quadratic inequalities in two variables, Graphing systems of quadratic inequalities, Conics - Parabola
Lessons
Quadratic Formula
For the quadratic equation: ax2+bx+c=0
the solutions are: x=2a−b±b2−4ac
For the quadratic equation: ax2+bx+c=0
the solutions are: x=2a−b±b2−4ac
- IntroductionSolve the equation using the quadratic formula:
2x2−12x+10=0 - 1.Solving a quadratic equation with TWO REAL SOLUTIONS
Solve using the quadratic formula: x2+10x+6=0 - 2.Solving a quadratic equation with ONE (REPEATED) REAL SOLUTION
Solve using the quadratic formula: 9x2+25=30x - 3.Solving a quadratic equation with TWO COMPLEX SOLUTIONS
Solve using the quadratic formula: −3x2−24x=49