Chapter R - Section R.4 - Factoring Polynomials - R.4 Exercises - Page 40: 89

$(m-2n)(p^4+q)$

Factoring the $GCF= (m-2n) ,$ the factored form of the given expression, $ p^4(m-2n)+q(m-2n) ,$ is \begin{array}{l}\require{cancel} (m-2n) \left( \dfrac{p^4(m-2n)}{m-2n}+\dfrac{q(m-2n)}{m-2n} \right) \\\\= (m-2n) \left( \dfrac{p^4(\cancel{m-2n})}{\cancel{m-2n}}+\dfrac{q(\cancel{m-2n})}{\cancel{m-2n}} \right) \\\\= (m-2n)(p^4+q) .\end{array}