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How to solve matrices
Verify that you have sufficient data.
In order to get a unique solution for each variable in a linear system using a matrix, you need to have as many equations as the number of variables that you are trying to solve. For example, with variables x, y and z, you would need three equations.
If you have four variables, you need four equations. If you have fewer equations than the number of variables, you will be able to learn some limiting information about the variables (such as x = 3y and y = 2z), but you cannot get a precise solution.