9n + 6m = 3(3n + 2m);
b² - ab = b(b - a);
b(a + 5) – c(a + 5) = (a + 5)(b - c);
20x³y² + 4x²y³ = 4x²y²(5x + y);
6(m - n) + s(n - m) = 6(m - n) -s(m - n) = (m - n)(6 - s).
1) 15х + 10y = 5(3x + 2y);
2) a² – ab = a(a - b);
3) n(7 - m) + k(7 – m) = (7 - m)(n + k);
4) 8m²n – 4mn³ = 4mn(2m - n²);
5) a(b - c) + 3(c - b) =a(b - c) - 3(b - c) = (b - c)(a - 3).