فضلا منكم أريد تصحيح هذا الكود

[badbadtoo]

Public Class Form1
Dim a As Double
Dim b As Double
Dim c As Double
Dim d As Double
Dim x1 As Double
Dim x2 As Double
Dim sqrt As Double
Private Sub Label4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label4.Click
End Sub
Private Sub TextBox4_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox4.TextChanged
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
a = TextBox1.Text
b = TextBox2.Text
c = TextBox3.Text
d = (b * b) - (4 * a * c)
If a = 0 And b = 0 Then
MsgBox("l’équation n’admet pas de solution ")
Else
If d < 0 Then
MsgBox("la solution est l'ensembl vide ")
Else
If d = 0 And a <> 0 Then
x1 = (-b) / a
TextBox4.Text = x1
Else
If d > 0 And a <> 0 Then
x1 = (-b + (Math.Sqrt(d))) / (2 * a)
x2 = (-b - (Math.Sqrt(d))) / (2 * a)
TextBox4.Text = x1
TextBox5.Text = x2
End If
End If
End If
End If
End Sub

[كعدان]

Public Class Form1
 Dim a As Double
 Dim b As Double
 Dim c As Double
 Dim d As Double
 Dim x1 As Double
 Dim x2 As Double
Private Sub Label4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label4.Click
End Sub
Private Sub TextBox4_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox4.TextChanged
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
 a = TextBox1.Text
 b = TextBox2.Text
 c = TextBox3.Text
 d = (b * b) - (4 * a * c)
 If a = 0 And b = 0 Then
  MsgBox("l’équation n’admet pas de solution ")
  Else
  If a = 0 And b <> 0 Then
   x1 = c / b
   TextBox4.Text = x1
   Else
   If d < 0 Then
    MsgBox("la solution est l'ensembl vide ")
    Else
     x1 = (-b + (Math.Sqrt(d))) / (2 * a)
     x2 = (-b - (Math.Sqrt(d))) / (2 * a)
     TextBox4.Text = x1
     TextBox5.Text = x2     
    End If
   End If
  End If
 End If
End Sub 

[badbadtoo]

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