Each state of the United States selects two senators to represent their states in the United States Senate. In 1913, the 17th Amendment[?] to the United States Constitution provided for the direct popular election of senators; prior to this, senators were selected by state legislatures.
... b/(2a) from both sides, we get
<math>x=\frac{-b}{2a}\pm\frac{\sqrt{b^2-4ac}}{2a}=\frac{-b\pm\sqrt{b^2-4ac}}{2a}.</math>
Generalizations
The formul ...