It is given in the question that,

OABC is a rectangle where O is the origin and OA = 5 units along x-axis

Also, AB = 3 units and B lies in the fourth quadrant

Now, coordinates of origin, O = (0, 0)

As point A lies on the x-axis

∴ Coordinate of point A = (5, 0)

Also, point B lies in the fourth quadrant

So, coordinate of point B will be negative

As the given width AB = 3 units

∴ Coordinates of point B = (5, -3)

Also, point C and O lies on the same line

Thus, abscissa of C = abscissa of O = 0

Similarly, Point C and B lies on the same altitude

Hence, both points have equal altitude

∴ Coordinates of C = (0, -3)

Hence, the coordinates of the vertices of the given rectangle are:

O (0, 0), A (5, 0), B (5, -3) and C (0, -3)