(14b²-c)/(7b) - 2b = (14*(0.5)²-(-14))/(7*0.5) - 2*0.5 = (14*0.25+14)/3.5 - 1 = (3.5+14)/3.5 - 1 = (17.5)/3.5 - 1 = 5 - 1 = 4.
Ответ: 4