RectangleGeometry

<Window x:Class="Workspace.DockExample"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Workspace" Width="700" Height="550">
          <Path Stroke="Red" StrokeThickness="1" Fill="#AACCFF">
            <Path.Data>
              <RectangleGeometry Rect="25,60 80 30" />
            </Path.Data>
          </Path>

</Window>

