Составить подпрограмму решения системы двух линейных алгебраических уравнений по правилу Крамера

program fun;
uses crt;
const s=4;
type a=array[1..s,1..s] of real;
var
a1,a2:a;
x,b:array[1..s] of real;
i,j,m,n:byte;
dx,dxx:real;
function det(a2:a):real;
var
y,z:a;
i,j,k:byte;
sum,d:real;
begin
for i:=1 to s do begin
y[i,1]:=a2[i,1];
z[i,i]:=1;
end;
for j:=1 to s do z[1,j]:=a2[1,j]/y[1,1];
for i:=2 to s do
for j:=2 to s do begin
if (j>=2) and (i>=j) then begin
sum:=0;
for k:=1 to j-1 do sum:=sum+y[i,k]*z[k,j];
y[i,j]:=a2[i,j]-sum;
end;
if (i>=2) and (j>=i) then begin
sum:=0;
for k:=1 to i-1 do sum:=sum+y[i,k]*z[k,j];
if y[i,i]<>0 then z[i,j]:=(a2[i,j]-sum)/y[i,i];
end;
end;
d:=1;
for i:=1 to s do d:=d*y[i,i];
det:=d;
end;
begin
clrscr;
writeln('a1');
for i:=1 to s do begin
write(' -->');for j:=1 to s-1 do read(a1[i,j]);
readln(a1[i,s]); end;
writeln('b');
for i:=1 to s do read(b[i]);
for n:=1 to s do
for m:=1 to s do a2[n,m]:=a1[n,m];
dx:=det(a2);
for j:=1 to s do begin
for n:=1 to s do
for m:=1 to s do a2[n,m]:=a1[n,m];
for i:=1 to s do a2[i,j]:=b[i];
dxx:=det(a2);
x[j]:=dxx/dx;
write('x',j,'=',x[j]:8:3);
end;
readkey;
end.

program kramer;
uses crt;
var
a,d:array[1..2,1..2] of integer;
b:array[1..2] of integer;
i,j,k:integer;
x1,x2,Y,t:real;
r:array[1..2] of real;
procedure anyk;
begin
for i:=1 to 2 do
for j:=1 to 2 do
x1:=(d[1,1]*d[2,2]+d[2,1]+d[1,2]);
x2:=(d[2,2]+d[1,1]+d[1,2]*d[2,1]);
Y:=x1-x2;
end;
procedure delta(k:integer);
begin
for i:=1 to 2 do
for j:=1 to 2 do
if j=k then d[i,j]:=b[i] else d[i,j]:=a[i,j];
end;
begin clrscr;
for i:=1 to 2 do
begin
for j:=1 to 2 do
begin
write(' a[',i,j,']=');
read(a[i,j]); end;
writeln; end;
for j:=1 to 2 do
begin
write('b[',j,']=');
readln(b[j]); end;
for i:=1 to 2 do
for j:=1 to 2 do
d[i,j]:=a[i,j];
anyk;
t:=Y;
delta(1);
anyk;
r[1]:=Y/t;
delta(2);
anyk;
r[2]:=Y/t;
for i:=1 to 2 do
writeln('x',i,'=',r[i]);
readln(i);
end.

function Korni(a1,b1,c1,a2,b2,c2:real;var x,y:real):boolean;
var d,d1,d2:real;
    f:boolean;
begin
d:=a1*b2-a2*b1;
f:=d<>0;
if f then
 begin
  d1:=c1*b2-b1*c2;
  d2:=c2*a1-a2*c1;
  x:=d1/d;
  y:=d2/d;
 end;
Korni:=f;
end;
var a,b,u,c,d,v,x,y:real;
    f:boolean;
begin
writeln('Введите коэффициенты a,b,u первого уравнения');
readln(a,b,u);
writeln('Введите коэффициенты c,d,v второго уравнения');
readln(c,d,v);
f:=Korni(a,b,u,c,d,v,x,y);
if f then writeln('x=',x:0:2,' y=',y:0:2)
else writeln('Система не определена');
end.