What is the focus of the parabola that has a vertex at (0, 0) and that passes through the points (–3, 3) and (3, 3)?
As #(+-3, 3) are equidistant from the y-axis, y-axis is the axis
of the parabola. O(0, 0) is the vertex. Therefore, its equation is
of the form
This passes through
The focus is on the axis x = 0, at a distance a = 3/4, from
the vertex (0, 0).
Thus the focus is