Well, we need to solve the inequality in terms of x...
-3(6-2x)≥4x+12 carry out indicated multiplication on left side
-18+6x≥4x+12 subtract 4x from both sides
-18+2x≥12 add 18 to both sides
2x≥30 divide both sides by 2
x≥15, in interval notation:
x=[15, +oo)
