1) (16a^2 - 8a + 1)/(1 - 4a + x - 4ax) = (4a - 1)^2 / (-(4a - 1) - x(4a - 1)) =(4a - 1)^2 /-(4a - 1)(x + 1) = (4a - 1)/-(x + 1) = (1 - 4a)/(x + 1)
2)(3x + xy^2 - x^2y - 3y)/(y^2 - x^2) = (xy(y - x) - 3(y - x))/(y - x)(y + x) = (y - x)(xy - 3)/ (y - x)(y + x) = (xy - 3)/(y + x)