Object drops vertically with a horizontal force acting on it

[MechaMZ]

Homework Statement

A couch cushion of mass m is released from rest at the top of a building having height h. A wind blowing along the side of the building exerts a constant horizontal force of magnitude F on the cushion as it drops as shown in the figure. The air exerts no vertical force.

http://img3.imageshack.us/img3/5868/p563.gif

If m = 1.22 kg, h = 8.48 m, and F = 2.42 N, how far from the building will the cushion hit the level ground?

Homework Equations

F=ma
x_f-x_i = v_it+0.5at²

The Attempt at a Solution

The time take for this situation should not be the same as an object is dropping vertically downward with 1.22kg, since there is a horizontal force acting on the current situation.
So I can't take the time as a common variable in between the free fall and this situation, but how to find out the variables?
the correct answer is 1.72 m

 

[Fightfish]

The time take for this situation should not be the same as an object is dropping vertically downward with 1.22kg, since there is a horizontal force acting on the current situation.
So I can't take the time as a common variable in between the free fall and this situation, but how to find out the variables?

Unfortunately, the time taken is the same, as the vertical and horizontal velocities are independent of each other. Whether the object is moving towards the right or left with whatever velocity does not change or affect the vertical motion of the object.