Go: package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
)

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextFloat64() (float64, error) {
	return strconv.ParseFloat(nextString(), 64)
}

func mathRound(f float64) float64 {
	return math.Floor(f + .5)
}

func round(x float64) float64 {
	if math.Abs(x) < 0.001 {
		return 0
	}
	return mathRound(x*1000) / 1000
}

func main() {
	scanner.Split(bufio.ScanWords)
	for {
		a, err := nextFloat64()
		if err != nil {
			break
		}
		b, _ := nextFloat64()
		c, _ := nextFloat64()
		d, _ := nextFloat64()
		e, _ := nextFloat64()
		f, _ := nextFloat64()

		detA := a*e - b*d
		x := (c*e - b*f) / detA
		y := (a*f - c*d) / detA

		fmt.Printf("%.3f %.3f\n", round(x), round(y))
	}
}

C++: #include <iomanip>
#include <iostream>
#include <vector>
#define N 2
 
using namespace std;
typedef vector< vector<double> > Equation;
 
bool input(Equation& c)
{
	if (!cin) return false;

    for (int i = 0; i < N; ++i)
        for (int j = 0; j < N + 1; ++j)
            cin >> c[i][j];
 
    return true;
}
 
int main()
{
    Equation c(N, vector<double>(N + 1));
	while (cin)
	{
		for (int i = 0; i < N; ++i)
			for (int j = 0; j < N + 1; ++j)
				cin >> c[i][j];

		// Gaussian elimination
		// 1. Forward elimination
        for (int i = 0; i < N - 1; ++i)
            for (int j = i + 1; j < N; ++j)
            {
                double d = c[j][i] / c[i][i];
                for (int k = i + 1; k <= N; ++k)
                    c[j][k] -= c[i][k] * d;
            }
 
		// 2. Back substitution
        for (int i = N - 1; i >= 0; --i)
        {
            double d = c[i][N];
            for (int j = i + 1; j < N; ++j)
                d -= c[i][j] * c[j][N];
            c[i][N] = d / c[i][i];
        }
 
        cout << setprecision(4) << fixed << c[0][N];
        for (int i = 1; i < N; ++i)
            cout << " " << c[i][N];
        cout << endl;
    }
 
    return 0;
}

C++:  #include <iostream>
#include <stdio.h>
#include <math.h>
using namespace std;
int main(){
    double a , b , c , d , e , f;
    while(cin >> a >> b >> c >> d >> e >> f){
    double t = a;
    a = a*d;
    b = b*d;
    c = c*d;
    d = d*t;
    e = e*t;
    f = f*t;
    double g = b-e;
    double h = c-f;
    double y = h/g;
    double x = (c- b*y) / a ;
    x = x * 1000;
    x = round(x);
    x = x/1000;
    y = y*1000;
    y = round(y);
    y = y/1000;
    printf("%.3lf %.3lf\n" , x  , y );
}
}

C++: #include <bits/stdc++.h>
#include <iostream>
#include <cstdio>
using namespace std;
#define j bai;
int main() {
	double a, b, c, d, e, y, x, f, bai;
	bool bo = false;
	while (cin >> a >> b >> c >> d >> e >> f) {
		if (a) {
			y = c / b;
			x = f / d - e*y;
		}
		if (b) {
			x = a / c;
			y = f / e - d*x;
		}

		if (d) {
			y = f / e;
			x = c / a - d*y;
		}
		if (e) {
			x = f / d;
			y = f / e - d*x;
		}
		else if (a < d) {
			bai = d / a;
			a *= j;
			b *= j;
			c *= j;
		}
		else {
			bai = a / d;
			d *= j;
			e *= j;
			f *= j;
		}
		if (((a > 0 && d < 0) || (a < 0 && d>0)) && bo == false) {
			y = (c + f) / (b + e);
			x = (c - b*y) / a;
		}
		else if (bo == false) {
			y = (c - f) / (b - e);
			x = (c - b*y) / a;
		}
		if (x == -0.000) {
			x = abs(x);
		}
		if (y == -0.000) {
			y = abs(y);
		}
		printf("%.3f %.3f\n", x, y);
	}
	return 0;
}

C++: #include <stdio.h>
#include <math.h>

int main(){
  int i = 0;
  while(1){
  i++;
  int a, b, c, d, e, f;
  scanf("%d ",&a);
  scanf("%d ",&b);
  scanf("%d ",&c);
  scanf("%d ",&d);
  scanf("%d ",&e);
  scanf("%d ",&f);
  
  double x, y;
  x = (double)(c*e-b*f) / (double)(a*e-b*d);
  y = (double)(a*f-c*d) / (double)(a*e-b*d);
  x = (double)round(x*10000.0) / 10000.0;
  y = (double)round(y*10000.0) / 10000.0;
  printf("%.3f %.3f\n", x, y);
  
  int line = ftell(stdin);
  if(scanf("%d", &a)==EOF) break;
  else{
    fseek(stdin, line, SEEK_SET);
  }
  }
  
  return 0;
}

C++: #include <iostream>
#include <vector>
#include <map>

using namespace std;

int main()
{
int a,b,c,d,e,f;
double A[2][2];
double B[2];
double inv_A[2][2];
scanf("%d %d %d %d %d %d",&a,&b,&c,&d,&e,&f);
int det = a*e-b*d;
A[0][0]=a; A[0][1] = b;
A[1][0]=d; A[1][1] = e;
B[0] = c;
B[1] = f; 

inv_A[0][0]=1.0/(double)det *A[1][1]; inv_A[0][1]=1.0/(double)det *-A[0][1];
inv_A[1][0]=1.0/(double)det *-A[1][0]; inv_A[1][1]=1.0/(double)det *A[0][0];

double res[2];
res[0]=0;
res[1]=0;

for(int i=0;i<2;i++){
for(int j=0;j<2;j++){
for(int k=0;k<2;k++){
res[i]+=inv_A[j][k]*B[k];
}
}
}

printf("%.3f %.3f\n",res[0],res[1]);
}

C++: #include <iostream>
#include <cstdio>

using namespace std;

int main(){
double a=1, b, c, d, e, f;

while(a){
cin >> a >> b>> c>> d>> e>> f;
double x, y;
x =(c*e-b*f) / (a*e-b*d);
y = (c*d-a*f) / (b*d-a*e);
printf("%.3f %.3f\n",x, y);
}

return 0;
}

C++: #include <iostream>
#include <vector>
#include <map>

using namespace std;

int main()
{
int a,b,c,d,e,f;
double A[2][2];
double B[2];
double inv_A[2][2];
while(~scanf("%d %d %d %d %d %d",&a,&b,&c,&d,&e,&f)){
int det = a*e-b*d;
A[0][0]=a; A[0][1] = b;
A[1][0]=d; A[1][1] = e;
B[0] = c;
B[1] = f; 

inv_A[0][0]=A[1][1]; inv_A[0][1]=-A[0][1];
inv_A[1][0]=-A[1][0]; inv_A[1][1]=A[0][0];

double res[2];
res[0]=0;
res[1]=0;


for(int j=0;j<2;j++){
for(int k=0;k<2;k++){
res[j]+=1.0/(double)det *inv_A[j][k]*B[k];
}
}

printf("%.3f %.3f\n",res[0],res[1]);
}
}

C++: #include<iostream>
using namespace std;
int main(){
  double a, b, c, d, e, f;
  double x, y;
  cin >> a >> b >> c >> d >> e >> f;
  x = (c * e - b * f) / (a * e - b * d);
  y = (a * f - c * d) / (a * e - b * d);
  cout << x << " " << y << endl;
  return 0;
}

C++: #include<stdio.h>
#include<math.h>
int main(void){
    double a,b,c,d,e,f,A,x,y,X,Y,Z;

    while(scanf("%lf%lf%lf%lf%lf%lf",&a,&b,&c,&d,&e,&f)!=EOF){
    A=a;
    a=a*d,b=b*d,c=c*d;
    d=d*A,e=e*A,f=f*A;
    if(b==e)y=0;
    else {Y=b-e,Z=c-f;
        y=Z/Y;
    }
    x=(c-b*y)/a;

    /*x=x+0.0005,y=y+0.0005;
    x=x*1000,y=y*1000;
    x=floor(x);
    y=floor(y);
    x=x/1000,y=y/1000;*/
    if(1e-10>fabs(x))x=0;
    if(1e-10>fabs(y))y=0;
   printf("%.3lf %.3lf\n",x,y);
    }
   //printf("\na%lf\nb%lf\nc%lf\nd%lf\ne%lf\nf%lf\n%lf\n%lf",a,b,c,d,e,f,Y,Z);

    return 0;
}

C++: #include<iostream>
#include<iomanip>
#define x_Formula(a,b,c,d,e,f) (c-(b*f)/e)/(a-(b*d)/e);
#define y_Formula(x,a,b,c) (c-(a*x))/b;

using namespace std;

double x;
double y;

void serch()
{
	int xx,yy;
	xx=x*10000;
	yy=y*10000;
	cout << xx << " " << yy << endl;
	if(xx>0)
		xx+=5;
	else
		xx-=5;
	if(yy>0)
		yy+=5;
	else
		yy-=5;
	x=xx/10000;
	y=yy/10000;
	cout << xx << " " << yy << endl;

}
int main()
{
	double num[6];
	int i;
	
	for(;cin >> num[0];)
	{
		for(i=1;i<6;i++)
			cin >> num[i];
		
		x=x_Formula(num[0],num[1],num[2],num[3],num[4],num[5])
		y=y_Formula(x,num[0],num[1],num[2])
		
		cout << setprecision(3);
		cout << setiosflags(ios::scientific);
		cout << fixed ;
		serch();
		cout << x << " " << y << endl;
	}
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<functional>
#include<iomanip>
using namespace std;
int main(){
	while (true) {
		double a, b, c, d, e, f;
		cin >> a >> b >> c >> d >> e >> f;
		if (cin.eof()) break;
		double x = (b * f - e * c) / (b * d - a * e);
		double y = (c * d - a * f) / (b * d - a * e);
		cout << setprecision(10) << fixed << x << " " << y << "\n";
	}
    return 0;
}

C++: #include <stdio.h>
#include <math.h>

int main(void)
{
  double a,b,c,d,e,f;
  while(scanf("%lf %lf %lf %lf %lf %lf", &a, &b, &c, &d, &e, &f) != EOF){
    double det = a*e-b*d;
    double x = round((e*c-b*f)/det*1000)/1000.0;
    double y = round((-d*c+a*f)/det*1000)/1000.0;
    
    printf("%.3f %.3f\n", x, y);
  }

  return 0;
}