Question

What is the factored form of x2 + 6x + 8?

Answer 1

one way:

look at the last number +8
write down all pairs of factors that multiply to give 8
1, 8
2, 4

is there any pair that add up to 6 ? YES 2 and 4
the factors are (x+2)(x+4)
you can multiply that out to check if it matches the original