Question

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

Answer 1

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]