What is the equation of the parabola with a vertex at the origin and a directrix of #y=1/4#?

1 Answer
Mar 11, 2016

The equation of parabola is #y= -x^2#

Explanation:

Equation of the Parabola in Vertex form is #y=a(x-h)^2+k# Here Vertex is at origin so h=0 and k=0 #:. y = a*x^2#The distance between vertex and directrix is #1/4# so #a=1/(4*d)=1/(4*1/4) =1#Here Parabola opens down. So #a=-1# Hence the equation of parabola is #y= -x^2# graph{-x^2 [-10, 10, -5, 5]}[Answer]