**Quadratic Equation**

**Basic Principles**

For all equations in form, we can have a solution to x.

**Properties of roots**

The square of all real numbers should be non-negative, so the square-root part is the most important part of the properties of the roots. We call this important part the discriminant, and is drawn as a triangle.

**Vieta's formulas**

The quadratic equation has many properties, not only what is mentioned before, and Vieta's formulas are one of them.

By adding and multiplying the roots, we get the above results, but still I would like to introduce one of the other ways.

For more, please read Vieta's Formulas.