Here is the problem: "A passenger in a convertible throws a ball up into the air. The car is going 35.0 m/s. The upward velocity of the ball is 8.00 m/s. Give the equations which specify the ball position at any given time with respect to the passenger (prime values) and respect to an observer on the road (un prime values)." Here is my problem . . . The teacher told us that in (x, y, z) and (x', y', z'), y and y' are the same. He told us that x = x' + vt and x' = x - vt. However, we weren't given t or t' so I cannot find x or x', and I absolutely have no clue how to find z or z'. Can someone give me hints or something? Thanks!