Can anyone me, with at least the first one?

3. r^2 + 2r - 35               4. a^2- 11a + 28
    (r + 7)(r - 5)                    (a - 7)(a - 4)

5. m^2 - 6m - 7                6. m^2 - m - 2
    (m + 1)(m - 7)                   (m - 2)(m + 1)

7. n^2 - 4n + 3                  8. b^2 - 4b - 5
    (n - 3)(n - 1)                       (b - 5)(b + 1)

Iwould say always for the both of them