Respuesta :

Simplifying,

[tex]\begin{gathered} (5u^2-u+7)+(-4u^2+2u+6) \\ \rightarrow5u^2-u+7-4u^2+2u+6 \\ \rightarrow5u^2-4u^2-u+2u+7+6 \\ \rightarrow u^2+u+13 \end{gathered}[/tex]