The equation of the parabola having vertex at origin and focus at 3,0

Given vertex is at origin, and the focus is 23,0Since the vertex of the parabola is 0,0 and the focus lies on the positive x - axis. the x- axis is the axis of the parabola while the  equation of  the parabola is of the form y2=4ax since the focus is 3,0, a=3Therefore, the equation of the parabola is y2=12x