When the factors of a trinomial are (x+p) and (x-q) then the coeffcient of the x term in the trinomial is?

The coefficient is:  "1" .

          Note:  There is an "implied coefficient" of "1"; since "1",  multiplied by any value, is equal to that exact same value; by convention, we eliminate the "1" as a coefficient.

Further explanation:

(x+p)(x−q) = x² − xq + px − pq ;


(x+p)(x−q) =  {using "FOIL" → "First, Outer, Inner, and Last" terms}:

First:    x*x = x² ;

Outer: x*(-q)= -xq ;

Inner:  p*x = px ;

Last:   p*(-q) = -pq

  (x + p)(x − q) = x² − xq + px − pq .