Ответ:\(x+18=45\)\(x=45-18=27\)\(y-27=16\)\(y=16+27=43\)\(3x=72\)\(x=72:3=24\)\(5y=135\)\(y=135:5=27\)Ответ: x = 27; y = 43; x = 24; y = 27.