To factor second-order polynomials, find factors of the constant term (8 in this case) that sum to the coefficient of the middle term (-6 in this case).
Since 8/2 = 4, 8/1 = 8, 8/-2 = -4, and 8/-1 = -8 are the only factors we can quickly see that the third option, 8/-2=-4 contains -2 and -4, which sum to -6
Therefore, we can factor this to be (x-4)*(x-2)
