ddd

No that doesn't change automatically because the x did. Here's an example..
X=2
Y=4

X can change to this X=4 but Y=4 stays the same unless they tell you they changed it. So therefore if X=Y then Y=Whatever number there is unless it states that
x=y & y=x

ddd:

If x = y then does y=x ?
I just get confused with all the letters and numbers put in one problem. They all get mixed up in my head..

Whenever I have a problem that is a bit confusing I swap the numbers or letters for easier things and then I can often see better what I am allowed to do.

x and y are letters, that is why it is confusing
so I am going to swap them for something else

1+4 = 8-3 that's true isn't it?
so lets look at
8-3 = 1+4 is that still true?

or
1/2 = 0.5
does 0.5=1/2?

or
2*8=16
does 16=2*8?

so
If x=y
does y=x?