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The set of all x satisfying the inequalities \(-4 \leq 2 - 3x \lt 7\) is

  • A.\(\left(2, \frac{5}{3}\right)\)
  • B.\(\left[2, \frac{5}{3}\right)\)
  • C.\(\left[\frac{-11}{3}, 2\right]\)
  • D.\(\left(\frac{-5}{3}, 2\right]\)
  • E.\(\left[\frac{-7}{3}, 2\right)\)

Answer: D

The solution set is \(\left(\frac{-5}{3}, 2\right]\).

Subtract 2 throughout, then divide by -3, which reverses both inequality signs:

\[ \begin{aligned} -4 \leq 2 - 3x &\lt 7 \\ -6 \leq -3x &\lt 5 \\ 2 \geq x &\gt -\tfrac{5}{3} \end{aligned} \]

So \(x\) runs from \(-\frac{5}{3}\) (excluded) to 2 (included). Intervals such as \(\left(2, \frac{5}{3}\right)\) come from forgetting to reverse the signs, which produces an empty, back-to-front interval; the -11/3 and -7/3 endpoints come from arithmetic slips.

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