(-p^3+6p^4+8p^2)+(10p^2+11p^4+9p^3)

(-p^3+6p^4+8p^2)+(10p^2+11p^4+9p^3)

-p^3+6p^4+8p^2+10p^2+11p^4+9p^3

-p^3+9p^3 +6p^4+11p^4 +8p^2+10p^2

8p^3 +17p^4 +18p^2