# How do you factor 9a^2 + 24a + 16 ?

$9 {a}^{2} + 24 a + 16 = \left(3 a + 4\right) \left(3 a + 4\right)$
I found this by noticing that $9 {a}^{2} = {\left(3 a\right)}^{2}$ and $16 = {4}^{2}$, then seeing what coefficient of $a$ came out when I multiplied $\left(3 a + 4\right) \left(3 a + 4\right)$.