Question 271325
Multiply by -1 to get:
x^2-6x+8
Now Reverse FOIL
What times what will give you x^2?
Answer: (x___)(x___) 
F:x^2
O
I
L

Next, what times what will give you 8 but added together will give you -6?
Answer: -2 times -4 will give you 8 and -2 + -4 will give you -6!
(x-2)(x-4)
F:x^2
O:-4x
I:-2x
L:8
Which gives you: x^2-4x-2x+8---add like terms----> x^2-6x+8  (look familiar?)

Now set them both equal to zero if asked to:
x-2=0   which is x=2
x-4=0   which is x=4