x^5 - 2x^4 + 5x^3 = x^3(x^2 - 2x + 5)
2a + 7xb - 2b - 7xa = a(2 - 7x) - b(2 - 7x) = (a - b)(2 - 7x)
a^2 - b^2 - 6a + 6b = (a - b)(a + b) - 6(a - b) = (a - b)(a + b - 6)
x^5 - 2x^4 + 5x^3 = x^3(x^2 - 2x + 5)
2a + 7xb - 2b - 7xa = a(2 - 7x) - b(2 - 7x) = (a - b)(2 - 7x)
a^2 - b^2 - 6a + 6b = (a - b)(a + b) - 6(a - b) = (a - b)(a + b - 6)