Imports System.Math
Imports System.Drawing.Graphics
Imports System.Drawing
Imports System.Drawing.Text
Imports System.EventArgs
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim x As Single
        Dim y As Single
        Dim xoff As Single
        Dim yoff As Single
        Dim penna As Pen = New Pen(Color.Red, 5)
        Dim pbgraphic As Graphics
        xoff = 100
        yoff = 100
        For x = -100 To 100
            y = x ^ 2
.....qui dovrei far si che il comando pen si attivasse e plottasse i valori X ed Y..... 
        Next
    End Sub
End Class