1. The problem statement, all variables and given/known data A jetliner flies at 960kmh^-1 relative to the air. it's going from Houston to Omaha, 1290km Northwards. At cruising altitude a wind is blowing east wards at 190kmh^-1. In what direction should the plane fly? How long will the trip take? 2. Relevant equations None 3. The attempt at a solution This is the part I am unclear: x-component: v' cos Θ + V = 0 y-Component: v' sin Θ + 0 = v I can understand why V is added to v' cos Θ: both are in the same x-direction. I don't understand the reason behind the y-component. Also, what is the reason for setting the equation to be zero?