1. The problem statement, all variables and given/known data Two coherent in-phase point sources of sound are located at the points (-2 m, 0 m) and (2 m, 0 m). If the wavelength of the sound is 0.9 m, at which of the following x values on the x-axis does destructive interference occur? 2. Relevant equations Wave Equation: y(x, t) = Acos(kx + ωt) 3. The attempt at a solution I have no idea how to even start this one. Could someone just nudge me in the right direction? This is the last practice problem I have to do, but I am really stuck.