(3x-1)^2-8(x+1)^2=(x+2)(x-2)
(3х-1)² - 8(х+1)² = (х+2)(х-2) 9х²-6х+1 - 8(х²+2х+1) = х²-4 9х²-6х+1-8х²-16х-8 = х²-4 х²-22х-7 = х²-4 х²-х²-22х = -4+7 -22х = 3 х = 3 : (-22) х = Ответ: .