3(t + 2) - t(t + 2) = (t + 2)(3 - t)
ab(b - 3) + a²(b - 3) = (b - 3)(ab + a²) = a(b - 3)(b + a)
c(c - d) + d(d - c) = c(c - d) + d(-c + d) = c(c - d) - d(c - d) = (c - d) (c - d)
k(m - 3n) - p(3n - m) = k(m - 3n) - p(-m + 3n) = k(m - 3n) + p(m - 3n) =
= (m - 3n)(k + p)
5(y + 3) - a(y + 3) - a(y + 3) - x(y + 3) = (y + 3)(5 - a - a - x) =
= (y + 3)(5 - 2a - x)
2(x - 4) + c(4 - x) - a(x - 4) = 2(x - 4) + c(-x + 4) - a(x - 4) =
= 2(x - 4) - c(x - 4) - a(x - 4) = (x - 4)(2 - c - a)