[BlindMath] Trouble With UEB

[dana mohsen]

Hello Blind Mathers,
Quick question: I'm currently learning math UEB and am using the APH
tutorial:
https://uebmath.aphtech.org/
However, I got stuck on the lesson discussing spatial arrangements (lesson
3.2). I'm confused by the use of the double-numerics, and, most of all, the
vertical and horizontal line indicators (dots5+dots 2 5 and dots 4 5 6,
respectively.)
How is spatial arrangement even helpful?
I hope I'm making some sense. :)
Best,
Dana