Which of the following quadratic expressions is factorable over the integers? Select all that apply.
(points)
x ^ 2 - 6x + 36
16x ^ 2 + 36x + 81
x ^ 2 - 10x + 25
4x ^ 2 + 12x + 9
4x ^ 2 - 49
x ^ 2 - 6x + 36
16x ^ 2 + 36x + 81
x ^ 2 - 10x + 25
4x ^ 2 + 12x + 9
None of the above expressions are factorable over the integers.