The figure below shows the given force system
$M_O = 480 \, \text{ N}\cdot\text{m}$
The force system above can be replaced by the following three force system shown below where the two pair into a couple which is the couple 480 N·m. The effect of these forces would be the same as the original system.
$240d = M_O$
$240d = 480$
$d = 2 \, \text{ m}$
The two opposing forces above will get canceled, thus, leaving a single force with the same effect as the three forces above which in turn has the same effect to the original system.
$(240 \sin 30^\circ)a = M_O$
$(240 \sin 30^\circ)a = 480$
$a = 4 \, \text{ m}$
$(240 \cos 30^\circ)b = M_O$
$(240 \cos 30^\circ)b = 480$
$b = 2.31 \, \text{ m}$
Thus, the equivalent single force is 240 N parallel to the given one and at a distance d = 2 m from O. The intercepts of this single force are A(-4, 0) and B(0, 2.31). answer