Х+6=49, у-50=28, 74-х=30
Х+6=49; Х=49-6; Х=43 У-50=28; у=28-50; у=-22 74-Х=30; -Х=30-74; Х=44
Х=49-6=43 у=28+50=78 х=74-30=44