How do you factor the expression x^2 + 9x + 8?

Apr 30, 2018

$\implies \left(x + 1\right) \left(x + 8\right)$

Explanation:

$\implies {x}^{2} + 9 x + 8$

We need to find two factors of $8$, such that the sum of the two factors is $9$.

Factors of $8$:

$\implies 1 , 8 \to 1 + 8 = 9$
$\implies 2 , 4 \to 2 + 4 = 6$

As we can see, the factors $1$ and $8$ give us a sum of $9$.

Hence,

$\implies {x}^{2} + 9 x + 8 = \left(x + 1\right) \left(x + 8\right)$