Option Explicit
Dim a#, b#, c#, x#, x1#, x2#

Private Sub Command1_Click()
a = Text1.Text
b = Text2.Text
c = Text3.Text
If a = 0 Then
x = -c / b
x1 = x
Text4.Text = x1
ElseIf a <> 0 & b * b - 4 * a * c = 0 Then
x = -b / 2 * a
x1 = x2 = x
Text4.Text = x1
Text5.Text = x2
ElseIf a <> 0 & b * b - 4 * a * c > 0 Then
x = -b + (b * b - Sqr(4 * a * c)) / 2 * a & x = -b - (b * b - Sqr(4 * a * c)) / 2 * a
x1 = x & x2 = x
Text4.Text = x1
Text5.Text = x2
ElseIf a <> 0 & b * b - 4 * a * c < 0 Then
x = "有虚根"
x1 = x
Text4.Text = x1

End If
End Sub

Private Sub Command2_Click()
End
End Sub

Private Sub Form_Load()

End Sub

哦.如果我要是求虚根你看这个语句可不.我不知道哪里又出问题了?
x1 = (-b) / (2 * a) & "+" & Sqr(-(b * b - 4 * a * c)) / (2 * a) & "i"
x2 = (-b) / (2 * a) & "-" & Sqr(-(b * b - 4 * a * c)) / (2 * a) & "i"

当然还是好人多嘛～～～，我还真的谢谢他的耐心呢，要都和你似的，一笑而过，我看我就的一哭半年了。。。。。

同感～～～