Factorizar :a?

<img src="https://tex.z-dn.net/?f=%20a%5E%7B2%7D%2Ba-ab-b%20" />

a(a + 1) - b(a + 1)

(a + 1)(a - b)

a(x + 1) - b(x + 1) + c(x + 1)

(x + 1)(a - b + c)

<img src="https://tex.z-dn.net/?f=%2081x%5E%7B2%7D%20-%28a-x%29%20%5E%7B2%7D%20" />

<img src="https://tex.z-dn.net/?f=%5B%289x%2B%28a-x%29%20-9x-%28a-x%29%5D%20" />

<img src="https://tex.z-dn.net/?f=%5B9x%2Ba-x%5D%20%5B9x-a%2Bx%5D" />

<img src="https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20-%20x%20-%2072" />

x - 9

x + 8 - 9x + 8x = - x

(x - 9)(x + 8)

<img src="https://tex.z-dn.net/?f=%28a%2B2%29%5E%7B2%7D%20-%20%28a-3%29%5E%7B2%7D%20%20" />

[ (a + 2) + (a - 3)] [(a + 2) - (a - 3)]

[ a + 2 + a - 3 ] [ a + 2 - a + 3 ]

[2a - 1] [ + 5].