(*ukazka zpracovani vstupniho testiku*)

SetDirectory[NotebookDirectory[]]

FileNames["*.xls"]

pom1=Import["koeficientyReal.xls"][[1]];
pom2=Drop[pom1,1];
MatrixForm[pom2];
praveStrany1=Last/@pom2;
praveStrany2=Transpose[pom2]//Last;
matice1=Transpose[Drop[Transpose[pom2],-1]];
matice2=Take[#,10]&/@pom2;
matice3=DeleteCases[pom2\[Transpose],praveStrany1]\[Transpose];

reseni1=Inverse[matice1].praveStrany1;
reseni2=LinearSolve[matice2,praveStrany2]
xka=Table[(Subscript[x, i]),{i,1,10}];
rovnicky1=Thread[matice1.xka==praveStrany1];
sol=Solve[rovnicky1,xka][[1]]
(Subscript[x, 5])+(Subscript[x, 3])/.sol
Thread[xka->reseni1]