Answer :
[tex]\begin{gathered} (ax+q)^2 \\ Rewrite_{\text{ }}the_{\text{ }}expresssion_{\text{ }}as\colon \\ (ax+q)^2=(ax+q)(ax+q) \\ Use_{\text{ }}distributive_{\text{ }}property\colon \\ ax^2+axq+axq+q^2=ax^2+2axq+q^2 \\ Let \\ mt=Middle_{\text{ }}term \\ so\colon \\ mt=2(ax\cdot q) \end{gathered}[/tex]
Therefore, the middle term is equal to: twice the product of the first term and the second term