1. The problem statement, all variables and given/known data When reacted with a small quantity of water, SiCl4 produces an oxychloride X, SixClyOz. The mass spectrum of X shows peaks at mass numbers 133, 149, 247, 263 and 396. You should assume that the species responsible for all these peaks contain the 16O, 35Cl and 28Si isotopes only. 2. The attempt at a solution The first step is fairly straightforward; the peak responsible for X is the 396 peak. Things start to get a little foggy when finding x, y and z. ##28x + 35y + 16z = 396## How can I go about solving such an equation without using some sort of time-consuming trial and error method?