I suspect it's something like reddit.com/r/riddles/comments/4ylgi0/comment/d6omol6

Not particularly elegant (ax^2 + bx + c where a = 1188/7, b = -726/7, c = 38), but certainly simple, yes.

Jryy, gurer hfrq gb or avar cynargf

For any two interior points (A and B), draw a line through them that intersects the triangle at C and D. Let E be a vertex such that CDE >= 90 degrees. Now AB <= CD, and CD <= CE (the hypotenuse of CDE), and CE <= x (because C, like the rest of the triangle, fits within a circle of radius x centered at E). So AB <= x.

A direct answer would pretty much give it away. Here's a hopefully less obvious hint: How would you construct a 3x3 multiplying magic square where the nine numbers could be any nine distinct positive integers?

A web search confirms that it is. merriam-webster.com/dictionary/tor

That's a minimum, but is it achievable? It's not obvious how to construct a list of assignments that maximizes efficiency.

By inference. "First three lines have some carets then :: then an equal number of carets; looks like code for 1 = 1, 2 = 2, 3 = 3. Next two lines look like code for 1 + 1 = 2, 4 + 3 = 7." And so on.

rot13(guerr gb gur cbjre vf gjbbarrvtugfrira), but I don't know how (gjbbarrvtugfrira gb gur cbjre bs bar) is meant to be ruled out.

Is it a zntvp rlr chmmyr?