In the OP, you presented this as an "equation solving" problem. We looked at your problem and observed that it appeared to us to be a curve fitting/regression problem to which we then applied the most common regression methodology -- linear least squares. Without know what the process is that generated the data or the methods used to model those kinds of processes, we were speaking rather naively about the problem. Of course, choice of regression algorithm, whether regression a good description of the problem, etc are all non-Excel questions that we are not always good at answering.

As for resources to better understand what regression generally (and linear least squares regression specifically), here's a link to a page at NIST (US government standards): https://www.itl.nist.gov/div898/hand...tion1/pmd1.htm that talks about process modeling.