[quote=“James37518, post:1, topic:25531”]
(Ignore the desktop screen on the right)
[/quote]
Next time, activate the window you wish to grab and then do ALT+PrintScreen to only grab the active window (instead of the whole desktop.) It is now on your clipboard. Paste it into a post in the forum, or into your favorite photo editor, etc. And you can also resize the SketchUp window for a min too reduce the size of the image here on the server. (le, look at all that wasted blue space.)
You can create two solids from the existing sides (the one to the left and the one at the top). Extend them to the full length of the shape. After grouping them, place them on top of each other and use the Intersection tool - that way only the area over which they intersect will remain, which will be the completed shape that you are looking to fill. It will also be a solid then too.