Question

When a trinomial is factored as (x+m)(x+n), what is the sum of m and n?

Answer 1

C. The coefficient of the x-term of the trinomial

Here is the reason why:
(x+m)(x+n)
x^2 + xm +xn + mn
x^2 + x(m+n) + mn
So, as you can see the sum of m and n is equal to the coefficient of the x-term of the trinomial.