Final answer:
The correct expression for 'W x 9 then add 5' is 'w x 9 + 5'. This is a two-step process where W is first multiplied by 9, and then 5 is added to the result.
Step-by-step explanation:
The expression that matches the statement "W x 9 then add 5" is D. w x 9 + 5. To explain this step by step, let's expand on the operation described. First, we multiply W (whatever value it may hold) by 9. Once that multiplication is done, we add 5 to the product. The correct mathematical expression for this process is w x 9 + 5. The other options presented, namely A, B, and C, all represent different operations which do not correspond to the original statement.