6.4-x=3.38x=6.4-3.38x=3.02检验:3.02+3.38=6.43.22/x=1.4x=3.22/1.4x=2.3检验:2.3*1.4=3.22 85+x=220x=220-85x=135检验:220-135=857x=98 x=98/7x=14检验:98/14=7
