Quadratic formula
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The quadratic formula is used to simplify the process of solving a quadratic equation. It is in the following form:
- <math>x = \frac{-b \pm \sqrt {b^2-4ac}}{2a}</math>
In order to be solved using this formula, a quadratic equation must be in the following format:
- <math>ax^2+bx+c=0\!</math>
You simply substitute <math>a</math>, <math>b</math>, and <math>c</math> into the formula.
You can prove that the formula is correct by substituting the formula in place of x in <math>ax^2+bx+c=0\!</math> and then gradually simplying the rather complicated formula that results, step by step. Eventually, if all the simplication steps are done correctly, it will simply to 0.