10 facts about parabolas

1. A parabola is a continuous curve that looks like an open bowl where the sides keep going up infinitely.
2. "Parabola" is from the Greek word meaning “exact application,” which, according to the Online Dictionary of Etymology, is “because it is produced by ‘application’ of a given area to a given straight line.”
3. All parabolas are vaguely “U” shaped and they will have a highest or lowest point that is called the vertex. Parabolas may open up or down and may or may not have x-intercepts and they will always have a single y-intercept
4. A quadratic equation (in x and y) is in standard form when it is written as y= ax² + bx + c → a isn’t equal 0
5. Every quadratic equation has a u-shaped graph, called a parabola
6. If the leading coefficient (the "a" in ax²) is positive, the parabola opens up.
7. If the leading coefficient is negative, the parabola opens down
8. The vertex has an x-coordinate of: -b/2a
9. To find the y-coordinate, just plug the x value into the quadratic equation and solve for y.
10. The VERTICAL line passing through the vertex is called the axis of symmetry. The equation for this line is: x=-b/2a