And here is one of the tips to get rid of formulas.
To make a family like folding doors those enable to close and open, Pythagorean theorem can be used for it like this
There must be several ways, this example is just one of them.
Point Hosted by Intersection
To eliminate formulas from this, 'Host Point by Intersection' in adaptive template is necessary.
And with this feature, you can make many interesting stuffs.
(This was really just for fun.)
You can download the umbrella here
And here is another useful example of using Host Point by Intersection.
In the Spanish Roof tiles that I posted before, I made the lowest batten with one different sweep from other battens. because the lowest one has to be bigger than others.
Other battens are included in the pattern family with a roof tile. so they could be rotated with tiles automatically. But there was no way I could find to make the last batten rotated the same except using Host Point by Intersection.
I drew a circle at the middle of the reference line, and placed a point for a workplane for a rectangle profile, and make it hosted by intersection with the reference line on the opposite side.
The reference line on the opposite side was out of the circle, but worked. Yes, Host lines don't have to have real intersections. When they don't, hosted points follow directions at least.