sat math question of the day

[elizabeth]

If , then which one of the following is negative?
(I)
(II)
(III)

(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I and III only

Thanks

[kadence]

All of the choices can be interpreted as quadratic inequalities with roots . The leading coefficient(s) for (I) and (III) are positive while for (II) is negative.

Therefore, for (I) and (III) we have the following sign diagram

---(+)--------{-4}---------(-)-------------{1}-------(+)---------

While for (II) we have the following sign diagram

---(-)--------{-4}---------(+)-------------{1}-------(-)---------

Therefore the correct answer is (E).


Hope these help!!

[elizabeth]

Thanks a lot for your reply!!