Hogy lehetne megoldani, hogy fusson?

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linken található 2. feladatról lenne szó.

A kódom:

unit unit3;

{$mode objfpc}{$H+}

interface

uses

Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls;

type

{ TForm1 }

TForm1 = class(TForm)

Button1: TButton;

EditA: TEdit;

EditB: TEdit;

LabelA: TLabel;

LabelB: TLabel;

LabelMo: TLabel;

LabelK: TLabel;

procedure Button1Click(Sender: TObject);

procedure EditAChange(Sender: TObject);

procedure LabelAClick(Sender: TObject);

private

{ private declarations }

public

{ public declarations }

end;

var

Form1: TForm1;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);

var a,b,x: real;

begin

on EDivByZero do

begin

ShowMessage('a nem lehet nulla');

LabelMo.Caption := '';

end;

procedure TForm1.EditAChange(Sender: TObject);

begin

end;

procedure TForm1.LabelAClick(Sender: TObject);

begin

end;

end.