Problem: An egg is thrown downwards at 2 m/s from the top of a bridge. At the same moment, a fisherman standing in a stream 30 m beneath the bridge throws a rock upwards at 15 m/s. How fast will the stone be moving when it and the egg are at the same height above the water? This is homework from chapters involving the kinematic equations, free fall, and projectile motion I know I first need to find the distance above the stream at which the rock and egg are at the same place at the same time but I don't know how to do this with the information given and the kinematic equations. I've tried solving using the down direction as positive and up as negative. I can't use displacement=Vi*t+1/2g*t squared for each and set them equal to each other because displacement may not be equal when the two objects meet (this comes out unsolveable when I've tried). I'm terribly stuck after several hours on this problem. How do I solve it? Thanks!