Factor each trinomial. Identify the binomial factors

X² + 5x - 6
X² - 10x + 21
X² + 15x + 36

1. X² + 5x - 6 = (x + 6)(x - 1)

2. X² - 10x + 21 = (x - 7)(x - 3)

3. X² + 15x + 36 = (x + 12)(x + 3)