Answer:
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Step-by-step explanation:

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X= 30
I don’t know if this is correct or not
I think you are missing part of the problem. If you had another equation or a value for x you could solve it.
To solve for c, you divide both sides by -18. If you do that, your answer will be -1/16. So, I think you typed the question wrong. Pretty sure it's the first option.
Answer:
In the expression of 7xy, if x is negative, then y must also be negative for the product to be positive.
Let me know if this helps!