| y2 = 4ax | y2 = -4ax | x2 = 4ay | x2 = -4ay |
As we can see above, in the first two example, when the y is
squared, the graph goes to left and right. Having p positive or negative decided which direction it will go. For the
other two equations algebraically, the x is squared and p also change signs. This transfer graphically because depending on
the sign of p it will either open up
or down.
The key parts of the parabola are the directrix, p value,
axis of symmetry, vertex, and focus. The axis of symmetry is a line that cuts
in between the parabola, perpendicular to the axis of symmetry is the
directrix. The focus is p, which is a
point inside the parabola. The distance from p to a point in the graph should
be the same from that point on the graph to the directrix. The p-value is also
important because if p is less than one the graph will look skinny if it is
greater than 1 it will become fatter.
Link to parabola explanation: ( http://youtu.be/-1MzoyzWxo4 )
<iframe width="420" height="315" src="//www.youtube.com/embed/-1MzoyzWxo4" frameborder="0" allowfullscreen></iframe>
3. Parabolas are everywhere, they are essentially a curved
line. Kicking a soccer ball is a parabola. The vertex of the path of the soccer
ball would be at the point where the soccerball is highest. One peal world
event where parabolas are used are in the reflectors in your flash light. “rays
emanating from the focus point will reflect off the parabola parallel to the
axis of symmetry.” (http://youtu.be/Djnwlj6OG9k)
4. works cited
http://youtu.be/Djnwlj6OG9k(
flashlight RWA)
http://www.mathsisfun.com/geometry/parabola.html
(picture of parabola)
