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.
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Answer:
x = -5
y = 4
Step-by-step explanation:
3x + 4y = 1 /*(-4)
4x + 5y = 0 /*3
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-12x - 16y = -4
12x + 15y = 0 +
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-y = -4
y = 4
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12x = -15y
12x = -60
x = -5
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