Break up v into components:
I chose up and right to be positive, so 
will be negative.
Using 
we will find the time t it takes for the supplies to go a horizontal distance x. Since x and y components are independent, the height doesn't matter when computing the distance moved in the x direction.
Now that we know t, we can find the velocity in the y direction that will cause the supplies to go a distance h in time t under acceleration -g. Plug in the value for t and and solve for v
