3(2-x)<-2/3(6x-21)

3(2-x) ≤ -2/3(6x-21) /*3 18 - 9x ≤ -12x + 42 -9x + 12x ≤ 42 - 18 3x ≤ 24 / : 3 x ≤ 8

3(2-x)<-2/3(6x-21) 6-3x<-4x+14 -3x+4x<14-6 x<8