A)7x+13x+256=556 b)357y-149y-8+224=624
7х+13х+256=556 20х=556-256 20х=300 х=300:20 х=15 357у-149у-8+224=624 208у=624-224+8 208у=408 у=408:208 у=1 200/208 у=1 25/26
7х+13х=556-256 20х=291 х=14,55