include<iostream>

include<cstdio>

include<cstring>

include<cmath>

using namespace std; double map1[1100][1100],ans[1100]; int main() { int n; cin>>n; for(int i=1;i<=n;i++) for(int j=1;j<=n+1;j++) cin>>map1[i][j]; for(int i=1;i<=n;i++) { int r=i; for(int j=i+1;j<=n;j++) if(fabs(map1[j][i])>fabs(map1[i][i])) r=j; if(r!=i) swap(map1[r],map1[i]); double div=map1[i][i]; if(!map1[i][i]) continue; for(int j=1;j<=n+1;j++) map1[i][j]/=div; for(int j=1;j<=n;j++) { if(i!=j) { div=map1[j][i]; for(int k=1;k<=n+1;k++) map1[j][k]-=map1[i][k]div; } } } for(int i=1;i<=n;i++) { int ans=0; for(int j=1;j<=n+1;j++) if(!map1[i][j]) ans++; if(ans==n&&map1[i][n+1]) { cout<<"-1"; return 0; } if(ans==n+1) { cout<<"0"; return 0; } } for(int i=n;i>=1;i--) { ans[i]=map1[i][n+1]; for(int j=i+1;j<=n;j++) ans[i]-=map1[i][j]ans[j]; } for(int i=1;i<=n;i++) { if(ans[i]==0) cout<<"x"<<i<<"=0"<<endl; else cout<<"x"<<i,printf("=%0.2f\n",ans[i]); } return 0; }