If one factor of x2 + 7x + 10 is (x + 2) then the other factor is:
(x - 5)
(x + 5)
(x + 4)
(x + 3)
x2 + 7x + 10
= x2 + 5x + 2x + 10
= x(x + 5) + 2(x + 5)
= (x + 2)(x + 5)