What can you simplify 12+3 (18-42) + 9

-51

Step-by-step explanation:

Step 1: Solve inside the parenthesis

12 + 3 (18 - 42) + 9

12 + 3 (-24) + 9

Step 2: Multiply

12 + 3 (-24) + 9

12 - 72 + 9

Step 3: Combine the first two numbers

(12 - 72) + 9

-60 + 9

Step 4: Combine the last two numbers

-60 + 9

-51

Answer: - 51