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J5WM? - ?T? - ?ML??

? = ((-12) + ((8 * 67) / 4) + ((-100) / 2)) / 24

? = Short abbreviation of the Royal Dutch Airline (3 letters, it is not RDA)
? = square root of 9

? = Last letter of the alphabet
? = \x51
? = \x51


Solution:
3 = ((-12) + ((8 * 67) / 4) + ((-100) / 2)) / 24

KLM = Short abbreviation of the Royal Dutch Airline (3 letters, it is not RDA)
3 = square root of 9

Z = Last letter of the alphabet
Q = \x51
Q = \x51

So the correct code was:
J5WM3-KLMT3-ZMLQQ

TG25?-26L?K-0R?E5

? = The square root of 16
? = The 14th letter of the alphabet
? = ((-12) + ((8 * 67) / 4) + ((-100) / 2)) / 8


Credits to Far #Scarce>Keemstar, for solving it
Solution:
4 = The square root of 16
N = The 14th letter of the alphabet
9 = ((-12) + ((8 * 67) / 4) + ((-100) / 2)) / 8

So the correct code was:
TG254-26LNK-0R9E5