Graphic Delphi

Title: Determine if three 2D Points are collinear to each other
Function Collinear(x1,y1,x2,y2,x3,y3:Double):Boolean;
Begin
Result := (((x2-x1)*(y3-y1)-(x3-x1)*(y2-y1))=0);
End;
(* End Of Collinear *)