uses
  GraphABC;

var
  a: array [,] of integer := ((80, 30), (170, 30), (170, 150), (80, 150));

begin
  MoveTo(a[0, 0], a[0, 1]);
  for i: byte := 1 to trunc(a.Length / 2 - 1) do
    LineTo(a[i, 0], a[i, 1]);
  LineTo(a[0, 0], a[0, 1]);
end.