The launching speed of a certain projectile is 5.2 times the speed it has at maximum height. What is the elevation angle at launching? Could someone just give me a starting point or a hint in the right direction? I know that the horizontal velocity doesn't decrease, and the vertical velocity is 0 at the maximum height. I can't put it together though; it seems like there isn't enough information given. How can you possibly tell by how much of a factor the speed is being affected by the vertical velocity, when you don't know the horizontal velocity?