Question 330068
n^3 + 9n^4 - 10n^2 - n^4 - 8n^3
..
group the similar terms
(9n^4-n^4)+(n^3-8n^3)-10n^2
8n^4-7n^3-10n^2

8n^4  8 coefficient n^4 variable
-7n^3 -7 co-efficient n^3 variable
-10n^2 -10 co-efficient n^2 variable