两边乘5
3{1\3[-3\4-(4\3-1)-x\2-3\4]-3\4]-17\4}=5-2x
-3\4-(4\3-1)-x\2-3\4-3\4-51\4=5-2x
-1\3-x\2-3\4-57\4=5-2x
3x\2=61\3
x=121\9