The vertex of the parabola y² + 6x $$-$$ 2y + 13 = 0 is

The coordinates of a moving point P are (2t² + 4, 4t + 6). Then its locus will be a/an

The locus of the middle points of all chords of the parabola y² = 4ax passing through the vertex is

$$\triangle \mathrm{OAB}$$ is an equilateral triangle inscribed in the parabola $$\mathrm{y}^2=4 \mathrm{a} x, \mathrm{a}>0$$ with O as the vertex, then the length of the side of $$\triangle \mathrm{O A B}$$ is