Which of the following shows how the number 7 can be rewritten with the difference of squares identity?
1.(16 - 9) = (4 + 3)(4 - 3)
2.(18 - 11) = (9 + 6)(9 - 5)
3.(25 - 4) = (5 + 2)(5 - 2)
4.(16 - 9) = -1(4 + 3)(4 - 3)
5.(64 - 1) = (8 + 1)(8 - 1)