If RadioButton1.Checked Then
        ElseIf TextBox1.Text = ("") And TextBox2.Text = ("") And TextBox3.Text = ("") Then
            MsgBox("Trois valeurs sont recquises minimum", MsgBoxStyle.Exclamation, "Pythagore Calculator")
        ElseIf TextBox1.Text = ("") And TextBox2.Text = ("") Then
            MsgBox("Trois valeurs sont recquises au minimum", MsgBoxStyle.Exclamation, "Pythagore Calculator")
        ElseIf TextBox1.Text = ("") And TextBox3.Text = ("") Then
            MsgBox("Trois valeurs sont recquises au minimum", MsgBoxStyle.Exclamation, "Pythagore Calculator")
        ElseIf TextBox2.Text = ("") And TextBox3.Text = ("") Then
            MsgBox("Trois valeurs sont recquises au minimum", MsgBoxStyle.Exclamation, "Pythagore Calculator")
        ElseIf TextBox1.Text.Trim.Length > 0 And TextBox2.Text.Trim.Length > 0 And TextBox3.Text.Trim.Length > 0 Then
            TextBox4.Text = Val(TextBox2.Text) ^ 2 - Val(TextBox3.Text) ^ 2
            TextBox4.Text = Val(TextBox4.Text) - Val(TextBox1.Text) ^ 2
            If TextBox4.Text.Trim.Length > 0 Then
                TextBox4.Text = ("Rectangle")
            ElseIf TextBox4.Text = ("Non Rectangle") Then
            End If
    End Sub