1points SPreCalc7 111042 Find an equation for the parabola t

1points SPreCalc7 11.1.042 Find an equation for the parabola that has its vertex at the origin and satisfies the given condition. Directrix y=-4 Need Help? L Read\".

Solution

Vertex = (h,k) = (0,0)

Directrix, y = -4 = k - 1/(4a)

-4 = -1/4a

a = 1/16

So, since this is
y = a(x - h)2 + k

y = 1/16(x - 0)^2+ 0

y = x^2/16 ---> ANSWER