ПОМОГИТЕ 900-(210+x)=36, 40+x+7=54,142-(123-x)+14=111

900-(210+x)=36900-210-x=36x=65440+x+7=54x=54-40-7x=7142-(123-x)+14=111142-123+x+14=11133+x=111x=111-33x=78

900-(210+х)=36900-210-х=36900-210-36=хх=65440+х+7=54х=54-40-7х=7142-(123-х)+14=111142-123+х+14=111х=111-142+123-14х=78