This answer uses NMF, which you can find out about on my profile:
Preliminary work:
Following the BIDMAS order of operations, we can calculate part of it already, and that's the 2•4, which equals 8.
Therefore, the equation now reads:
8+x = y
x = 5:
8+5 = 13
13 ≠ 16
13 ≠ y
x = 4:
8+4 = 12
12 = 12
12 = y
Therefore, the pair is (4, 12)
