Factor : y² + 6y + 8
Basically, all you have to do is plug in random numbers.
I'm pretty sure that there is an easier way to do it, but I haven't been taught that yet, so for me, guessing & checking would be the best way to get your answer.
The answer I got after tons of failed attempts was :
(y + 2)(y + 4)
~Hope I helped!~