12б+74б

It looks like you wrote an algebraic expression (or perhaps you were adding numbers) with a mistake—there is no operation specified between "12б" and "74б". If you meant to add or multiply these two terms, you'd need to clarify the terms or provide the operation. In the Cyrillic alphabet, "б" is not a number, so if it's a variable (like "x" or "y" in English), then the expression represents two terms that can only be combined if they are like terms.

If "б" is intended to be a variable, then:

• For addition, you would have: \( 12б + 74б = 86б \)
• For multiplication, you would have a different situation entirely, where each "б" is treated as a variable, and you'd multiply the coefficients (12 and 74) to get: \( 12б \cdot 74б = 888б^2 \) (assuming here "б" is a variable and can be squared).

If "б" means something else or you're using it to signify a different concept, please provide more context or clarify so that I can assist you properly.