Respuesta :

[tex]\bf \begin{array}{lll|l} 12m(r+t)^2&~\hspace{4em}&~3pr(r+t)^4\\&&\\ 4\cdot \underline{3} m\underline{(r+t)^2}&&3pr(r+t)^{2+2}\\&&\\ &&\underline{3} pr(r+t)^2\underline{(r+t)^2} \end{array}~\hfill \stackrel{\textit{\Large GCF}}{3(r+t)^2}[/tex]