Необходимо сравнить результаты метода Гаусса с точкой пересечения прямых на графике - Turbo Pascal

uses crt;
const num=5;
var a: array [1..num,1..num] of real;
    b, x: array [1..num] of real;
    n, i, j, k: integer;
       delenie: real;
begin
 clrscr;
 writeln('Введите колич-во неизвестных величин:');
 readln(n);
 writeln;
 writeln('Вводите коэфф-ты матpицы A по стpокам нажимая ENTER:');
  for i:=1 to n do
   begin
    for j:=1 to n do
        read(a[i,j]);
   end;
   writeln;
   writeln('Введите вектоp В свободных членов:');
    for i:=1 to n do
     read (b[i]);
  writeln;
  writeln('Расширеная матрица:');
  for i:=1 to n do
   begin
    for j:=1 to n do
        write (a[i, j]:5:3,' ':2);
        write (b[i]:5:3,' ':2);  
        writeln;
   end;
    for i:=1 to n-1 do
      begin
       for k:=i+1 to n do
        begin
         delenie:= a[k,i] / a[i,i];
          for j:=i+1 to n do
              a[k,j]:= a[k,j] - a[i,j] * delenie;
              b[k]:= b[k] - b[i] * delenie;
        end;
     end;
    for i:=n downto 1 do
     begin
      for j:= i+1 to n do
          b[i]:= b[i] - a[i,j] * x[j];
          x[i]:= b[i] / a[i,i];
     end;
    writeln;
    writeln('ОТВЕТ:');
    for i:=1 to n do
     writeln('X[',i:1,']=', x[i]:1:2);
   readkey;
end.

uses graph;
function F1(x:real):real;
begin
F1:=5+x
end;
function F2(x:real):real;
begin
F2:=-7-2*x
end;
var a,b,m:real;
    x,x1,y1:real;
    x0,y0,i:integer;
    s,s1:string;
begin
x0:=0;
initgraph(x0,y0,'');
a:=-16;
b:=10;
x0:=getmaxX div 2;
y0:=getmaxY div 2;
m:=(y0-40)/F1(b);
line(x0-round(17*m),y0,x0+round(17*m),y0);{оси}
line(x0,0,x0,getmaxY);
for i:=1 to 16 do
 begin
  line(x0-3,y0-round(i*m),x0+3,y0-round(i*m));
  line(x0-3,y0+round(i*m),x0+3,y0+round(i*m));
  line(x0+round(i*m),y0-3,x0+round(i*m),y0+3); 
  line(x0-round(i*m),y0-3,x0-round(i*m),y0+3);
  if i mod 2=0 then
   begin
    
    str(i,s);
    outtextXY(x0-25,y0-round(i*m),s);
    outtextXY(x0-30,y0+round(i*m),'-'+s);
  
    outtextXY(x0+round(i*m),y0+10,s);
    outtextXY(x0-round(i*m)-10,y0+10,'-'+s);
   end;
 end;
 
outtextXY(x0+round(16*m),y0-20,'X');
outtextXY(x0+5,10, 'Y');
 
x:=a;
setcolor(12);
while x<=b do
 begin
  if x=a then moveto(x0+round(x*m),y0-round(F1(x)*m))
  else lineto(x0+round(x*m),y0-round(F1(x)*m));
  x:=x+0.1;
 end;
x:=a;
setcolor(10);
while x<=b do
 begin
  if x=a then moveto(x0+round(x*m),y0-round(F2(x)*m))
  else lineto(x0+round(x*m),y0-round(F2(x)*m));
  if abs(F1(x)-F2(x))<0.01 then
   begin
    x1:=x;
    y1:=F1(x);
   end;
  x:=x+0.1;
 end;
setcolor(14);
setfillstyle(1,14);
fillellipse(x0+round(x1*m),y0-round(y1*m),3,3);
{название}
setcolor(12);
outtextXY(10,80,'y=5+x');
setcolor(10);
outtextXY(10,100,'y=-7-2x');
setcolor(14);
str(x1:0:1,s);
str(y1:0:1,s1);
outtextXY(10,120,'x='+s+'  y='+s1);
readln
end.