To solve the equation \(-x^2 - 3.5 = -12.5\), we can first simplify it.
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Add 3.5 to both sides: \[ -x^2 - 3.5 + 3.5 = -12.5 + 3.5 \] This simplifies to: \[ -x^2 = -9 \]
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Multiply both sides by -1: \[ x^2 = 9 \]
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Take the square root of both sides: \[ x = \pm 3 \]
Thus, the real solutions are: \[ { -3, 3 } \]
So the correct response is: \({ -3, 3 }\) (left brace negative 3 comma 3 right brace).