15*х+47, 5-(100*х-12) при х =0, 7
15·х+47, 5–(100·х–12) при х =0, 7 15·х+47, 5–(100·х–12) =15*x+47.5-100x+12=-85*x+59.5=-85*0.7+59.5=-59.5+59.5=0 Ответ: 0