SOLUTION: it says, "Identify each curve. find the characteristics listed." 12x= y^2 vertex, focus, directix please help

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: it says, "Identify each curve. find the characteristics listed." 12x= y^2 vertex, focus, directix please help      Log On


   



Question 667898: it says, "Identify each curve. find the characteristics listed."
12x= y^2 vertex, focus, directix
please help

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
it says, "Identify each curve. find the characteristics listed."
12x= y^2 vertex, focus, directix
*
y^2=12x
This is an equation of a parabola that opens rightwards.
Its standard form: (y-k)^2=4p(x-h), (h,k)=(x,y) coordinates of the vertex
For given equation: y^2=12x:
vertex: (0,0)
axis of symmetry: y=0
4p=12
p=3
focus: (3,0) (p-distance from vertex on axis of symmetry)
directrix: x=-3 (equation of vertical line p-distance from vertex on the axis of symmetry
see graph below:
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C-%2812x%29%5E.5%2C%2812x%29%5E.5%29+