Given the sum of the functions expressed as:
[tex]\mleft(5x+3\mright)+x^2-8x+4[/tex]Collecting the like terms:
[tex]x^2+5x-8x+3+4[/tex]Group the terms based on their degrees
[tex]x^2+(5x-8x)+(3+4)[/tex]Simplify the result to determine the final answer:
[tex]\begin{gathered} x^2+(5x-8x)+(3+4) \\ x^2+(-3x)+7 \\ x^2-3x+7 \end{gathered}[/tex]Hence the required sum of the functions is x^2 - 3x + 7