1. The problem statement, all variables and given/known data An oscillating system of a block attached to a string where k = 400 at some time t has a position x of 0.1 m, velocity of -13.6 m/s, and accel. of -123 m/s^2. Find the amplitude of the motion. Do not use energy. 2. Relevant equations x = Acos(wt + phi) v = -Awsin(wt + phi) a = -Aw^2cos(wt + phi) 3. The attempt at a solution I can solve for omega by using sqrt(-a / x), we still have 3 unknowns A, t, and phi. We have 3 equations, but they are not linear equations so I don't know how to solve them simultaneously. What other method is there that I can use since I can't use energy?