How to replace subfolder and querystring in url?

Hi
I want to change http://localhost:1190/Project/Subfolder/Default.aspx?Query=1
to
http://localhost:1190/Project/Images/Image.jpg
Tried somewhat below, no success:
Request.Url.AbsoluteUri.Replace(Request.Url.AbsolutePath, "") + @"/Images/Image.jpg"));
...