Advanced Math practice question

Answer: A. 2 < x < 4

x² − 6x + 8 = (x − 2)(x − 4), which is negative exactly between its zeros, 2 and 4.

Why the other answers are wrong

B. x < 2 or x > 4

Outside the zeros the product of two same-sign factors is positive.

C. x < 4

x < 2 makes both factors negative and the product positive.

D. x > 2

x > 4 makes the product positive.

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