Q. 14

  1. p^2q - pq

\Rightarrow p(pq - q)

\Rightarrow pq(p - 1)

  2. 5x^2 + x - 4

\Rightarrow 5x^2 + 5x - 4x - 4

\Rightarrow 5x(x + 1) - 4(x + 1)

\Rightarrow (5x - 4)(x + 1)