Respuesta :

Answer:

1/9

Step-by-step explanation:

Answer:

Step-by-step explanation:

Please write this as y = (1/2)x^2 for greater clarity.  (1/2) is the coefficient of x^2 here.  

The applicable form for the equation of this quadratic is 4py = x^2.  

Your y = (1/2)x^2  becomes 2y = x^2.  Therefore, 4p = 2, or p = (1/2).

Thus, the focus is (0, 1/2) (just above the vertex, (0, 0) ), and the equation of the directrix is y = -1/2.