Answer:
The answer is the last line.
Explanation:
Use the quadratic formula
a = 1
b = -a
c = a^2 - b
x = -b +/- sqrt(b^2 - 4ac)
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2a
x = a +/- sqrt(a^2 - 4(1)*(a^2 - b)
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2
x = a +/- sqrt(a^2 - 4a^ + 4b)
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2
x = a +/- sqrt(4b - 3a^2)
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2