Final answer:
The simplified expression is 1 + w when assuming w9 represents w multiplied by 9. If there's a typo and w9 means w raised to the power of nine, it wouldn't cancel and would remain in the expression.
Step-by-step explanation:
The expression provided can be simplified to 1 + w. This is because when you distribute the 9 inside the brackets to each term, you will get 9(-w) - 9(8), which simplifies to -9w - 72. Adding w to the expression gives you -9w - 72 + w, which simplifies further to -8w - 72 when you combine like terms. Finally, adding 9 to the expression gives you a result of -8w - 63. However, there might be an error in your question, as the option d) 9 - w - 8 + w9 suggests w9 could be w × 9 or w^9 instead of just w as we assumed here based on the surrounding context. If w9 stands for w multiplied by 9, the correct answer should be 1, since -9w + 9w cancel each other out. If w9 indicates w raised to the power of nine, that would not cancel and the term would remain in the final expression.