-7小于等于5分之【2乘上（1-3x）】小于等于45

-7<=[2*(1-3x)]/5<=9
-35<=2*(1-3x)<=45
-35/2<=1-3x<=45/2
-35/2-1<=-3x<=45/2-1
-18.5<=-3x<=21.5
-21.5/3<=x<=18.5/3

-43/6<=x<=37/6

原式＝－35<＝2－6x<＝225
＝－37<＝－6x<＝223
＝－223/6<＝x<＝37/6
<=是小于等于

X大于等于负的6分之253同时小于等于6分之37

-7<=2*(1-3x)/5<=45

-35<=2*(1-3x)<=225

-35/2<=(1-3x)<=225/2

223/2<=3x<=-33/2

-223/6<=x<=37/6

-7 ≤ 2(1-3x)/5 ≤ 9
-35 ≤ 2(1-3x) ≤ 45
-35/2 ≤ 1-3x ≤ 45/2
-37/2 ≤ -3x ≤ 43/2
-43/2 ≤ 3x ≤ 37/2
-43/6 ≤ x ≤ 37/6