Ответ: 5х^2+14х-3 = 0D = 14^2 — 4•5•(-3)= 196 + 60 = 256√D = +-16×1 = (-14+16)/(2•5) == 2/10 =0,25х1=1×2 = (-14-16)/(2•5) =-35x^2 + 14x — 3 == (5х-1)(х+3)