Ну вот, как-то так:
Код:
const
n=7;
var
a,b,c1,c2,c: array [1..n,1..n] of integer;
i,j,k: byte;
begin
Randomize;
writeln('Matrix A:');
for i:=1 to n do
begin
for j:=1 to n do
begin
A[i,j]:=random(20);
write(a[i,j]:8);
end;
writeln;
end;
writeln('Matrix B:');
for i:=1 to n do
begin
for j:=1 to n do
begin
b[i,j]:=random(20);
write(b[i,j]:8);
end;
writeln;
end;
writeln('Matrix C:');
for i:=1 to n do
for j:=1 to n do
begin
c1[i,j]:=0;
c2[i,j]:=0;
end;
for i:=1 to n do
for j:=1 to n do
for k:=1 to n do
begin
c1[i,j]:=c1[i,j]+a[i,k]*b[k,j];
c2[i,j]:=c2[i,j]+b[i,k]*a[k,j];
end;
for i:=1 to n do
begin
for j:=1 to n do
begin
c[i,j]:=c1[i,j]+c2[i,j];
write(c[i,j]:8);
end;
writeln;
end;
readln
end.