Question

factor each expression
$r^2 + 12r + 27$

Explanation:

Step1: Identify $a,b,c$ for $ax^2+bx+c$

For $r^2+12r+27$, $a=1$, $b=12$, $c=27$

Step2: Find pair summing to $b$, product $c$

Find two numbers: $9+3=12$, $9\times3=27$

Step3: Write factored form

$(r+9)(r+3)$

Answer:

$(r+9)(r+3)$