Making a string that adapts itself to the text inside it
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Im making a program to solve second grade equation (2x²+2x+2 for example)and i was trying to make the user input the whole equation in a text box,the computers stores whats written on the textbox in a string and then for a equation like 
2x²+2x+2 the coeficients are 2,2 and 2 and are stored in the string on locations 0,4 and 7.The big problem is what if its a bigger equation like 32x²+32x+45 or 123x²+45x+6 ?That way wont work,anyone knows how to do it?
The code for now:

    
Public Class Form1
    Dim i1 As Double
    Dim i2 As Double
    Dim i3 As Double
    Dim delta As Double
    Dim x1 As Double
    Dim x2 As Double
    Dim leters As String


    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        i1 = T1.Text
        i2 = T2.Text
        i3 = T3.Text
        delta = (i2 * i2) - 4 * (i1 * i3)
        If (delta < 0) Then
            Ld.Text = delta
            L1.Text = "Impossível"
            L2.Text = "Impossível"
        Else
            x1 = (-i2 + Math.Sqrt(delta)) / (2 * i1)
            x2 = (-i2 - Math.Sqrt(delta)) / (2 * i1)
            Ld.Text = delta
            L1.Text = x1
            L2.Text = x2

        End If
    End Sub

    
    Private Sub RadioButton1_CheckedChanged(sender As System.Object, e As System.EventArgs) Handles RadioButton1.CheckedChanged
        GroupBox1.Text = "Equação"
        GroupBox1.Width = 200
        GroupBox1.Height = 58
        T1.Width = 188
        T3.Hide()
        T2.Hide()
        Label1.Hide()
        Button1.Hide()
        Button2.Show()


    End Sub

    Private Sub RadioButton2_CheckedChanged(sender As System.Object, e As System.EventArgs) Handles RadioButton2.CheckedChanged
        GroupBox1.Text = "Coeficientes"
        GroupBox1.Width = 200
        GroupBox1.Height = 143
        T1.Width = 119
        T3.Show()
        T2.Show()
        Label1.Show()
        Button1.Show()
        Button2.Hide()

    End Sub

    Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
        leters = T1.Text
        leters.ToString()



    End Sub    

    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

    End Sub
End Class


