PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

إذا أضعفت يكون لكلّ وتر منها ثلاثة صحيح ‘when doubled are divisible by three (multiples of 1 1/2)’

Arabic

References: Alm. MS Leiden: f. 7r
Translation of:
Greek: ὅσαι δὶς γινόμεναι τρίτον μέρος ἕξουσιν [Alm. Heiberg: I.10, 42:10]
Synonyms:
إذا أضعفت كان لها ثلث[Alm. MS Tunis: ]