Решение системы линейных уравнений методом Гаусса

uses
crt;
const
e = 0.000001; { точность вычислений }
var
a,a1: array[1..10, 1..10] of real;
b,b1: array[1..10] of real;
x: array[1..10] of real;
n, i, j, k: integer;z, r, g: real;
begin
clrscr;
n:=3;
A[1, 1] := 2.16; A[1, 2] := 1.96; A[1, 3] := 1.56;
A[2, 1] := 3.55; A[2, 2] := 3.23; A[2, 3] := 2.78;
A[3, 1] := 4.85; A[3, 2] := 4.47; A[3, 3] := 3.97;
b[1] := 13.16; b[2] := 21.73; b[3] := 29.75;
writeln('Матрица A: ');
for i := 1 to n do
begin
for j := 1 to n do
begin
write(a[i,j]:5:2);
a1[i,j]:=a[i,j];
end;
writeln;
end;
writeln;
Writeln('Матрица B: ');
for i:=1 to n do
writeln(b[i]);
for k := 1 to n do { прямой ход Гаусса }
begin
for j := k + 1 to n do
begin
r := a[j, k] / a[k, k];
for i := k to n do
begin
a[j, i] := a[j, i] - r * a[k, i];
end;
b[j] := b[j] - r * b[k];
end;
end;
for k := n downto 1 do { обратный ход Гаусса }
begin
r := 0;
for j := k + 1 to n do
begin
g := a[k, j] * x[j];
r := r + g;
end;
x[k] := (b[k] - r) / a[k, k];
end;
writeln('Корни системы:');
for i := 1 to n do
write('x[', i, ']=', x[i]:0:2, '   ');
end.