рещи уравнения. x+18=60+27; x-23= 31-19; (40+60)-x=19; x+(20+71)=100

х+18=60+27х=60+27-18х=69;х-23=31-19х=31-19+23х=35;(40+60)-х=19100-х=19х=81;х+(20+71)=100х+91=100х=9.