Final answer:
The expression (4 + 5/)(4-5) simplifies to -9.
Step-by-step explanation:
The expression (4 + 5)(4-5) can be simplified using the distributive property. First, add 4 and 5 together to get 9. Then, multiply 9 with the difference of 4 and 5. The difference of 4 and 5 is -1, so the expression becomes 9(-1). Multiplying 9 and -1 gives -9 as the final answer.
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