Who is @d? One-Letter username joined Feb 2022! Only one post? Followed by Ivanka Trump and other notables. Recently tagged by @kash links in comments.
(media.greatawakening.win)
Think mirror.
With two mirrors at 90 degrees (perpendicular to each other and the original) you will get 3 images (360/90) = 4-1 = 3. If horizontal and vertical bars are mirrors "_" and "|" and "q" is the original, that would produce three images that look like this:
b...d
... __
p.|.q
Ignore the dots, I used them for formatting. It's tough to show this properly with the way this interface handles text, but hopefully I have explained it sufficiently. If not let me know.
d
q
Yes, that's the two. Now add one more mirror 90 degrees to the horizontal one and you get three images as shown above. I.e. from a "q" with two mirrors you get the image of "d", "p", and "b" as shown.