Question

What interval includes all possible values of x, where –3(6 – 2x) ≥ 4x + 12? (–∞, –3] [–3, ∞) (–∞, 15] [15, ∞)

Answer 1

$-3(6- 2x) \geq4x + 12\\\\-18+6x\geq4x+12\\\\2x\geq30\\\\x\geq15\\\\x\in[15,\infty)$

So, the last one.