Let’s consider sets of linear algebraic equations in Mathcad in vector-matrix form , whereis quadratic matrix of coefficients which go together with unknown variables, matrix determinant has non-zero value; х is vector of unknown variables; – vector of absolute terms. The solution is as follows. If the determinant of matrix has non-zero value, then matrix is invertible. In this case we multiply the left and the right member of the original equation by the inverse matrix , and get a solution, that looks like: . It is not complicated to realize these procedures with help of Mathcad instruments. In case of the infinite set of solutions we get a singular matrix, and Mathcad generates the answer: “” and guns the calculations. In the listing you can observe an example of a set of linear algebraic equations being solved.