Как отметить точку пересечения прямой с осью х - VB

Private Sub Command1_Click()
Dim i As Double
Picture1.Scale (-2.213, 6.31)-(3.5, -3)
Picture1.Line (-1, 0)-(3.5, 0)
For i = -1 To 4
Picture1.Line (i, 0.1)-(i, -0.1), vbRed
Picture1.Print i
Next i
Picture1.Line (0, 7)-(0, -3)
For i = -3 To 7
Picture1.Line (0.1, i)-(-0.1, i), vbRed
If i <> 0 Then Picture1.Print i
Next i
For i = 2 To 3 Step 0.1
Picture1.Line (i, f(i))-(i + 0.1, f(i + 0.1))
Next
Picture1.Line (2, f(2))-(2, 0), vbGreen
Picture1.Line (3, f(3))-(3, 0), vbGreen
For i = 1 To ind
Picture1.Line (arr(i), f(arr(i)))-(arr(i), 0), vbGreen
Picture1.Line (brr(i), f(brr(i)))-(brr(i), 0), vbGreen
Next i
End Sub