Answer:
Use the completing the square method
which is
(x+ (b/2))^2 - (b/2)^2 + c
x^2+6x+8 = 0
a = 1 b = 6 c = 8
b/2 = 3
(x+3)^2 - 9 + 8 = 0
becomes
(x+3)^2 -1 = 0
which becomes
(x+3)^2 = 1
ADDITIONAL:
i don’t know why they said (x-h) since there are no negatives in this
let me explain
(x-h) ^2 is the same as (x-h)(x-h) which leaves us with
x^2 - 2xh + h
but the equation we start with is
x^2 + 6x + 8 = 0
look at the signs
the middle term’s one is different