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# Data Sufficiency: Plugging into Yes/No Data Sufficiency

Is $$y^{-x}$$ negative? >(1) $$y$$ is positive. >(2) $$x$$ is negative.
Correct. [[snippet]] Stat. (1): Since $$y$$ is positive, the fraction $$y^{-x}$$ is positive, so the answer is a definite "No." That is a definite answer, so **Stat.(1) → No → S → AD**. Stat. (2): You know that $$x$$ is negative, but that tells you nothing about $$y$$. * If you __Plug In__ $$y=3$$ and $$x=-3$$, then you get a positive number: >>$$y^{-x} = 3^{-(-3)} = 3^3 = 27$$. * If you __Plug In__ $$y=-3$$ and $$x=-3$$, then you get a negative number: >>$$y^{-x} = (-3)^3 = -27$$. There is no definite answer, so **Stat.(2) → Maybe → IS → A**.
Incorrect. [[snippet]] The base determines the sign when using exponents.
Incorrect. [[snippet]] Stat. (1): Since $$y$$ is positive, the fraction $$y^{-x}$$ is positive, so the answer is a definite "No." That is a definite answer, so **Stat.(1) → No → S → AD**.
Incorrect. [[snippet]] Stat. (2): You know that $$x$$ is negative, but that tells you nothing about $$y$$. * If you __Plug In__ $$y=3$$ and $$x=-3$$, then you get a positive number: >>$$y^{-x} = 3^{-(-3)} = 3^3 = 27$$. * If you __Plug In__ $$y=-3$$ and $$x=-3$$, then you get a negative number: >>$$y^{-x} = (-3)^3 = -27$$. There is no definite answer, so **Stat.(2) → Maybe → IS → ACE**.
Statement (1) ALONE is sufficient, but Statement (2) alone is not sufficient to answer the question asked.
Statement (2) ALONE is sufficient, but Statement (1) alone is not sufficient to answer the question asked.
BOTH Statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
EACH statement ALONE is sufficient to answer the question asked.
Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.