(9c - 5c^4) + (2c + 4c^4) - (3c + 8c^2 + 7c^4)

(9c - 5c^4) + (2c + 4c^4) - (3c + 8c^2 + 7c^4)

9c - 5c^4 + 2c + 4c^4 - 3c - 8c^2 - 7c^4

9c+ 2c - 3c + 4c^4 - 5c^4- 7c^4 - 8c^2

8c - 8c^4 - 8c^2