function [x] = eliminacja(n)

[A,b]= macierz_c(n);
x=zeros(n,1);

for k=1:n-1
    l=zeros(n,1);
    for i=k+1:n
        l(i,1)=(A(i,k))/(A(k,k));
    end
    for i=k+1:n
        b(i)=b(i)-b(k)*l(i);
        for j=k:n
            A(i,j)=A(i,j)-A(k,j)*l(i);
        end
    end
end

for k=n:-1:1
    S=0;
    for j=k+1:n
        S=S+A(k,j)*x(j);
    end
    x(k)=(b(k)-S)/A(k,k);
end