calculate the following and show work

12-(-4)-9=

I'll be glad to check your answer.

(-4)-9=5

12-5=7

I don't like the way Tom did this

proper way:

12 - (-4) - 9
= 12 + 4 - 9
= 16 - 9
= 7

To calculate the expression 12 - (-4) - 9, we need to follow the order of operations, also known as PEMDAS (Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction).

Step 1: Simplify the double negatives within parentheses.
-(-4) = 4

After simplifying within the parentheses, the expression becomes:

12 + 4 - 9

Step 2: Perform addition and subtraction from left to right.

12 + 4 = 16

16 - 9 = 7

Therefore, the value of 12 - (-4) - 9 is 7.