1. The problem statement, all variables and given/known data I have a problem here and I just can't seem to figure it out. The problem is, A ball is thrown horizontally from a height of 24.28 m and hits the ground with a speed that is 4.0 times its initial speed. What was the initial speed? 2. The attempt at a solution I've found the velocity in the y-direction by using the equation v^2 = vo^2 + 2 a x, the velocity is 21.81 m/s. I've found the time it takes for the ball to drop using the equation v = vo + a t, t comes out to be 2.22s. But here on out, I don't know what to do next, i know that vx is constant and acceleration is zero in the x-direction, but I'm unable to get anything more. Any help will be appreciated, thanks in advance!