Is origin x or y

Answer 1

Depending on the sort of system your are using origin can either be 0 , (0,0) , (0,0,0) , etc.

0 for when you have only one axis 0x , so when x = 0 you have the origin.

(0,0) for when you have two axis system 0x , 0y , when x=0 and y=0 as well.

and so on and so forth.