Answer: unfactorable
Step-by-step explanation: To factor x² - 8x - 16, we set up our two binomials with x and x as the first position in each binomial.
To fill the second position, we want to
look for factors of -16 that add to -8.
Factors of -16
+16 · -1
-16 · +1
+8 · -2
-8 · + 2
+4 · -4
So what pair of factors add to -16.
Well, none of them do.
When that happens, we say that the original
trinomial is unfactorable and that's your answer.
