Answer:
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.