А) 12х^3 - 22х^2 - 20х = 2х(6х^2 - 11х - 10) = 2x(6x^2-15x+4x-10) = 2x((6x^2-15x) + (4x - 10)) = = 2x(3x(2x-5) + 2(2x-5)) = 2x(3x+2)(2x-5)
б) 80my^2 - 12my - 8m = 4m(20y^2 - 3y - 2) = 4m(20y^2 - 8y + 5y - 2) = 4m ((20y^2 - 8y) + (5y-2)) = 4m (4y(5y - 2) + (5y - 2)) = 4m(4y + 1)(5y - 2)