When you factor out -1 from a trinomial?

Answer 1

just make the trinomial easier to factor.

ex -x2 + 3x + 4 ... most books don't teach you how to factor when a leading term is negative. ... so -1(x2- 3x- 4) ... now factor again ignoring the -1

-1(x - 4)(x + 1)

Answer 2

The same way as with positive numbers. The absolute values are the same.

1, -1, 2, -2, 4, -4, 8, -8 are the factors of -8.

Answer 3

Change all the signs in the trinomial and then proceed as normal.