Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim dblTaxableIncome As Double

        dblTaxableIncome = CDbl(txtInput.Text)
        Calculate(dblTaxableIncome)

    End Sub
    Private Sub Calculate(ByVal dblTaxableIncome As Double)
        Dim dblTaxesDue As Double = 0


        If dblTaxableIncome > 0 And dblTaxableIncome <= 7150 Then
            dblTaxesDue = dblTaxableIncome * 0.1
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        ElseIf dblTaxableIncome > 7150 And dblTaxableIncome <= 29050 Then
            dblTaxesDue = 715 + (dblTaxableIncome * 0.15)
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        ElseIf dblTaxableIncome > 29050 And dblTaxableIncome <= 70350 Then
            dblTaxesDue = 4000 + (dblTaxableIncome * 0.25)
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        ElseIf dblTaxableIncome > 70350 And dblTaxableIncome <= 146750 Then
            dblTaxesDue = 14325 + (dblTaxableIncome * 0.28)
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        ElseIf dblTaxableIncome > 146750 And dblTaxableIncome <= 319100 Then
            dblTaxesDue = 35717 + (dblTaxableIncome * 0.33)
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        ElseIf dblTaxableIncome > 319100 Then
            dblTaxesDue = 92592.5 + (dblTaxableIncome * 0.35)
            lstOutput.Items.Add("Your federal tax due is " & FormatCurrency(dblTaxesDue, 2) & ".")

        Else
            MsgBox("Something Broke. Was your input a number? If not, try again.")
        End If
    End Sub
End Class