A parabola opens upwards if its general equation is of the form x^2 = 4ay and sidewards if its general equation is of the form y^2 = 4ay.

For y^2 = 4ax, the vertex is (0,0). For any other vertex (x0, y0) the
equation is of the form (y - y0)^2 = 4a(x - x0). So you can determine the
vertex by seeing where the parabola intersects the axis. The focus is a point
inside the parabola at a distance *a* from the vertex and lying on the
axis.

The ends of the latus rectum are points of a chord drawn through the focus, parallel to the directrix which end on the parabola. For a parabola opening upward, they would have the same y-coordinate as the focus and the x-coordinate would be +2a and -2a.

For x^2 + 8y = 0 => x^2 = -8y=> a = -2

**The parabola opens in the downwards direction. The vertex is (0,0).
The focus is (0,-2) and the ends of the latus rectum are (4, -2) and (-4,
-2).**

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