posted by Boobear .
(5t^4 + 6t^3 – 3t^2 + 4t - 11) - (-9t^4 – 6t^3 + 5t^2 + 3t + 8)
1. Remove the 1st parenthesis without
changing any of the terms.
2. Since there is a negative sign in front of the 2nd parenthesis, remove it
by changing the sign of each term.
3. Combine like-terms.