Answer:
no sign
Step-by-step explanation:
The value of the product is ...
[tex]-9\times\dfrac{0}{-3}=\dfrac{-9\cdot 0}{-3}=0[/tex]
The value 0 has no sign. It exists between positive and negative numbers. It is neither positive nor negative.
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We prepend a minus sign to negative numbers. The value 0 is usually written without such a sign, so might be considered to have a sign of +, just because it isn't –.