Final answer:
The expression that is equivalent to 3x-12 223-56x is -53x + 211.
Step-by-step explanation:
To find the expression that is equivalent to 3x-12 223-56x, we can combine like terms. The -12 and 223 are constants, so we can add them together to get 211. The variables with the same exponent can be combined as well, so we have 3x-56x = -53x. Therefore, the equivalent expression is -53x + 211.