Set 17: Linear Inequalities (Advanced)

Choice B is correct. Choice B is the correct answer. Isolating negative variable terms requires careful sign management. 1. Subtract 9: $9- 3 x - 9 < 0 - 9$, giving $-3 x < -9$ 2. Divide by -3: $\frac{-3 x}{-3} > \frac{-9}{-3}$ (REVERSE the sign!) 3. Simplify: $x > 3$ Strategic Tip: Dividing both sides by a negative coefficient ALWAYS reverses the inequality direction. Choice A is incorrect because it fails to reverse the inequality when dividing by -3. Choice C is incorrect because it uses the wrong sign on the boundary value. Choice D is incorrect because while it reverses the sign correctly, the boundary value should be 3, not -3.