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The solution set of the inequality \(6(2x + 3) + x \gt 53 - 2x\) is

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

Answer: A

The solution set is \(\left(\frac{7}{3}, \infty\right)\).

\[ \begin{aligned} 6(2x + 3) + x &\gt 53 - 2x \\ 12x + 18 + x &\gt 53 - 2x \\ 15x &\gt 35 \\ x &\gt \tfrac{7}{3} \end{aligned} \]

Dividing by the positive number 15 does not reverse the inequality, so every \(x\) greater than \(\frac{7}{3}\) works. The set \(\left(-\infty, \frac{7}{3}\right)\) reverses the sign, and the bounded intervals add a limit the inequality does not have.

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