Then, since the point B is the centre of the circle CGH,BC is equal to BG.
Again, since the point D is the centre of the circle GKL, DL is equal to DG. And in these DA is equal to DB;
therefore the remainder AL is equal to the remainder BG. [C.N. 3]
But BC was also proved equal to BG;
therefore each of the straight lines AL, BC is equal to BG.
And things which are equal to the same thing are also equal to one another; [C.N. 1]
therefore AL is also equal to BC.
卽甲庚線、與乙丙線等。
論曰。丁戊、丁庚線。同以丁為心。戊、庚、為界。故等。界說十五於丁戊線減丁丙。丁庚線減丁甲。其所減兩腰線等。則所存亦等。公論三
夫丙戊、與丙乙。同以丙為心。戊、乙、為界。亦等。界說十五
卽甲庚、與丙乙等。公論一。 (p. 二四)
See previous Chinese sentence
See above