Answer:
One pair of equivalent expressions is:
x - 3y + 12
12 - 3y - 2x + x + 2x
Second,
x + 3y + 12
3x + 2y - 2x + y + 12
third,
3y + 12
x + 3y + 2x - 3x + 7 + 5
four,
3x + y - 12
4y + 3y + 3x - 6y - 10 - 2
Explanation:
In order to match the equivalent expressions we have to put each expression in its simplest form
So,

One pair of equivalent expressions is:
x - 3y + 12
12 - 3y - 2x + x + 2x
Second,
x + 3y + 12
3x + 2y - 2x + y + 12
third,
3y + 12
x + 3y + 2x - 3x + 7 + 5
four,
3x + y - 12
4y + 3y + 3x - 6y - 10 - 2
..