1. The problem statement, all variables and given/known data A bridge rises 321 m above the water. Supposed Jack kicks the rock horizontally off the bridge. The magnitude of the rock's horizontal displacement is 45.0 m. Find the speed at which the rock was kicked. 2. Relevant equations Kinematics I think? v = vo + at Δx = vot + 0.5at2 v2 = vo2 + 2aΔx 3. The attempt at a solution Well, to start off I tried to divide it into x and y components: x direction vo = ? v = ? Δx = 45 a = 0 t = ? t found: 8.09 sec y direction vo = 0 v = ? Δx = 321 m a = 9.8 m/s2 t = ? t found: 8.09 sec So then I tried finding t (which would be the same for both): 321= 0.5(9.8)t2 t = 8.09 But what to do know? What would be the initial velocity of the rock? Please help, thanks everyone!