in math, when is the order (x,y) and when does the y come first like (y,x)?

Answer 1

(a,b) is called an ordered pair
using (x,y) instead of (y,x) is just a convention. as long as you are consistent, (x,y) is equivalent to (y,x). the important thing is not what letters (symbols) are used but which position corresponds to which axis. i believe (x,y) is so common for the same reason that (x,y,z) and (i,j,k) are common: they are alphabetical and, hence, easy to remember.

Answer 2

If the examinar asked you just question then its means that the order is (x,y) and when he specifically said you to set the order of expression ASC (order x,y) or DESC (order y,x). However, when we solve al-gebric expressions the order of expression should be ASC or DESC for example when solving the squreroot (underoot) of al-gebric expression it is necessry the expression should be in ASC or DESC order while adding or subtracting the expressions, order is not necessry, just add/subtract exponents (power) with exponents.

Example : x^2 + y^2 - 2xy (an al-gebric expression - not sorted)
x^2 - 2xy + y2 ( sorted in x,y order)
y^2 -2xy + x^2 ( sorted in y,x order)

The order of (x,y) or (y,x) are accprding to the exponents (powers)

Answer 3

I don't believe y ever comes before x when you are talking about an ordered pair representing a point on the Cartesian plane.

Answer 4

Really, there is no way that an ordered pair become (y,x). However, there is a such thing as an inverse. When you take an inverse of an ordered pair, then you would swich the numbers around. For example, the inverse of (9,1) would be (1,9).

Answer 5

its always (x,y). that way people don't have to memorize when its x,y and when its y,x!
but you may be thinking of a reflection over the origin...
to reflect x,y over the origin
x' (the new x) is y (the old y) and
y' (the new y) is x (the old x)

by the way x' is called x prime if you are wondering and yes x'' is x double prime

Answer 6

It never comes first