Final answer:
The expression 2(-12r - 3) + (42 - {}) simplifies to -24r + 36 - {}.
Step-by-step explanation:
To simplify the expression 2(-12r - 3) + (42 - {}), we can start by simplifying the multiplication: 2(-12r - 3) = -24r - 6. Next, we can simplify the addition and subtraction: -24r - 6 + 42 - {} = -24r + 36 - {}. Since we don't have enough information about {}, we cannot simplify the expression any further. Therefore, the expression 2(-12r - 3) + (42 - {}) is equivalent to -24r + 36 - {}.