Smart way to align orientation constrained edge with another edges angle

I’ve not found a good solution for this problem:

It seems like i should be able to snap to cursor rotation but there isnt an option that I can find to do it.
Anyone know of a smart way to solve this?

Hmm, because the new poly only has/can match the angle you have to contruct it yourself. You can duplicate the reference poly snap on vertex (left screenshot) and cut duplicated and resized This edge to construct the new poly with tinyCAD addon:

(or just move the copied ref poly with (Shift-S) to Selection to Cursor and resize edges because you have to construct the new poly anyway) .

Copying over the face to get the angle seems to be the easiest way. Move with edge snap then gets the intersection point.
Thanks for taking the time to help! :smiley: