Is it two objects intersecting? If it is one object, you could duplicate it, then scale it so that the inner edge of the duplicate is on the outside edge of the origional. Then use the difference boolean to to take off the corners. This would be useful if you need to take off more than one corner.
In the end, after you inpired me (thank you all!!), here's what I did:
1) I duplicated both polygons
2) Used Boolean > Intersection so that I got a small piece which would serve as a "cap" for my corner, with the correct angle:
3) I then moved the end vertices from both polygons so that they would "hide" inside the cap:
4) And then got my final result:
I believe that's not the best way to do it. I guess I could perfect the end result by trimming the end of both polys using a copy of the cap for each one (then using Boolean > Difference), and then unite the three resulting objects.
But that worked for my needs....
Thank you all for your help.
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