Answer:
-5 or 5 depending on how you write the simplified form
Step-by-step explanation:

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The applicable rules of exponents are ...
(a^b)(a^c) = a^(b+c)
1/a^b = a^-b
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Some folks like their simplified form to contain only positive exponents. Other folks avoid unnecessary fractions. Choose the form that satisfies your grader.
The area needed is at least 170.5 ft².
Let w = the width of the rectangular area.
Because the length is 15.5 ft, therefore the calculated area should be at least 170.5 ft². That is
(15.5 ft)*(w ft) ≥ 170.5 ft²
w ≥ 170.5/15.5
w ≥ 11 ft
Answer: w ≥ 11 ft
Multiply 6 by 60 then divide by two which will get you 180.