This list of rivers of the Americas includes all the major rivers of the Americas. See each article for their tributaries, drainage areas, etc. Unusually significant tributaries appear in this list, under the river into which they drain.
... a single fraction; the common denominator is 4a2. We get
<math>\left(x+\frac{b}{2a}\right)^2=\frac{-4ac+b^2}{4a^2}=\frac{b^2-4ac}{4a^2}.</math>
Taking ...