-3(x-2)≥4-x-3x +6 >= 4-x 2x <= 2 x <= 1(1+2x)/3>x-11+2x > 3x-3x< 4 合并为x <= 1
-3(x-2)≥4-x-3x+6≥4-xx≤1(1+2x)/3>x-11+2x>3x-3x<4所以x≤1