1. The problem statement, all variables and given/known data A guitar string has a fundamental frequency of 429 Hz when its tension is 259 N. The string is being tuned to a fundamental frequency of 388 Hz. What is the required tension? 2. Relevant equations v = sqrt(T/u): where v is the speed, T is the tension and u is the linear mass density f1 = v/2L: where f1 is the fundamental frequency, v is the speed again and L the length of the string 3. The attempt at a solution sqrt(T/u) = f1(2L) sqrt(259/u) = 858L I tried to use the speed equations to find u or L, which would allow me to calculate the v after and then get the frequency, but I'm still left with 2 unknowns. Am I using the wrong equations to solve this?