<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="WpfApplication1" Height="352" Width="334" WindowStartupLocation="CenterScreen">
<StackPanel>
<Polygon Fill ="AliceBlue" StrokeThickness ="5"
Stroke ="Green"
Points ="40,10 70,80 10,50" />
</StackPanel>
</Window>