Given:
[tex]\begin{gathered} A=5x^2-5x+1 \\ B=2x^2+9x-6 \end{gathered}[/tex]Addition is given by,
[tex]\begin{gathered} A+B=(5x^2-5x+1)+(2x^2+9x-6) \\ A+B=5x^2+2x^2-5x+9x+1-6 \\ A+B=7x^2+4x-5 \end{gathered}[/tex]Answer:
[tex](5x^2-5x+1)+(2x^2+9x-6)=7x^2+4x-5[/tex]