You need to upload those to the internet. The links you provided are only locally relevant. If you take a look on the toolbar above the post textbox, you will see a paperclip icon. You can click on that and it will popup a new window that will allow you to attach an image.

There is an icon that looks like a mountain with a square sun (apparently web developers don't get out enough to see the sun is actually roundish), in that window you can put a link to an image already on the intertubes. Such as form a place like ImageShack® - Hosting